repo stringlengths 8 123 | branch stringclasses 178 values | readme stringlengths 1 441k ⌀ | description stringlengths 1 350 ⌀ | topics stringlengths 10 237 | createdAt stringlengths 20 20 | lastCommitDate stringlengths 20 20 | lastReleaseDate stringlengths 20 20 ⌀ | contributors int64 0 10k | pulls int64 0 3.84k | commits int64 1 58.7k | issues int64 0 826 | forks int64 0 13.1k | stars int64 2 49.2k | diskUsage float64 | license stringclasses 24 values | language stringclasses 80 values |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
himarygr/apache-superset-charts-js | main | # Custom Superset Charts
This repository contains custom charts for Apache Superset
## Example of card charts
| 💪📊 This repository contains custom charts for Apache Superset | echarts,javascript,superset,barchart,chart-library,echarts4,echarts5,ant-design,antv | 2023-08-08T12:53:41Z | 2023-11-11T14:29:26Z | null | 1 | 0 | 25 | 0 | 0 | 6 | null | null | JavaScript |
iAdamo/alx-higher_level_programming | main | ## **Higher Level Programming**
#### **`Python`** | **`MySQL`** | **`JavaScript`** | **`ORM`**
#### **PROJECTS:**
- [Python - Hello, World](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x00-python-hello_world)
- [Python - if/else, loops, functions](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x01-python-if_else_loops_functions)
- [Python - import & modules](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x02-python-import_modules)
- [Python - Data Structures: Lists, Tuples](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x03-python-data_structures)
- [Python - More Data Structures: Set, Dictionary](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x04-python-more_data_structures)
- [Python - Exceptions](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x05-python-exceptions)
- [Python - Classes and Objects](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x06-python-classes)
- [Python - Test-driven development](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x07-python-test_driven_development)
- [Python - More Classes and Objects](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x08-python-more_classes)
- [Python - Everything is object](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x09-python-everything_is_object)
- [Python - Inheritance](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x0A-python-inheritance)
- [Python - Input/Output](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x0B-python-input_output)
- [Python - Almost a circle](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x0C-python-almost_a_circle)
- [SQL - Introduction](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x0D-SQL_introduction)
- [SQL - More queries](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x0E-SQL_more_queries)
- [JavaScript - Warm up](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x12-javascript-warm_up)
- [JavaScript - Objects, Scopes and Closures](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x13-javascript_objects_scopes_closures)
- [Python - Object-relational mapping](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x0F-python-object_relational_mapping)
- [Python - Network #0](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x10-python-network_0)
- [Python - Network #1](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x11-python-network_1)
- [JavaScript - Web scraping](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x14-javascript-web_scraping)
- [JavaScript - Web jQuery](https://github.com/iAdamo/alx-higher_level_programming/tree/main/0x15-javascript-web_jquery)
#### Author: **`Adam Sanusi Babatunde`**
| Higher Level Programming | javascript,mysql,object-oriented-programming,python3,object-relational-mapping,python-network | 2023-08-08T01:57:25Z | 2024-01-15T02:58:07Z | null | 1 | 0 | 441 | 0 | 1 | 6 | null | null | Python |
tofl/Figue | master | # Figue
Figue is an **experimental** frontend micro-framework written in Javascript.
The idea for this project came to my mind after discovering the [Strawberry framework](https://github.com/18alantom/strawberry) and [this conference](https://www.youtube.com/watch?v=85gJMUEcnkc) on the virtual DOM, although I ended up not adding a vDOM to the framework.
Although I've been using frontend frameworks for years (mainly Vue.js, but also React and Angular to some extent), they had always felt like incomprehensible tools. As I was studying their internals, I started to question why these frameworks exist in the first place, and why we can't use native Javascript more often.
I believe these frameworks serve two main purposes:
- A functional purpose: the Web API was not as developed then as it is now. It made sense, at the time, to add the possibility to use components for example. However, nowadays, many of the tools that exist in frontend frameworks like React natively exist in the browser.
- A practical purpose: frameworks impose certain guidelines and help making the codebase more maintainable and understandable. This makes sense as websites can be extremely complex.
The first point, the functional concern, is the one Figue aims to address. By developing Figue, I want to see if there are viable, simpler and lightweight alternatives to today's most famous frameworks.
---
## Advantages of Figue
- Reactive
- No build process, just import the script
- Super lightweight, no dependencies
- No virtual DOM
## Installation
### Using a link
The best way of importing Figue is by simply getting the latest version of the package using unpkg.com, like so:
```
<script src="https://unpkg.com/@tofl/figue@latest/index.js"></script>
```
Note: you **must** wait for your HTML structure to be loaded before calling the script.
### Importing Figue as a package
If your project is an app that is served via an application bundler or a server, you can use npm to install Figue. First, run the install command:
```
$ npm i @tofl/figue
```
Then, import it as a module:
```javascript
<script type="module">
import '@tofl/figue';
</script>
```
## Usage
### Initialisation
To initialize the app, simply use the `initFigue()` function after importing the framework as shown above. It takes in a CSS selector as its only argument and returns an `_` object.
```javascript
const _ = initFigue('html');
```
### Adding reactive state
You can declare reactive state and methods by simply adding keys to the `_` object.
```javascript
const _ = initFigue('html');
_.firstname = 'John';
_.lastname = 'Doe';
```
Then, just call these properties from the template by using curly braces:
```html
<p>Hello, {{ firstname }} {{ lastname }}. Welcome back.</p>
```
### Manage events
It is very easy to handle common events with Figue. Simply append an event handler to the `_` object in the script section and reference the event name as an attribute starting with an `@` (and the event handler as its value) in the template.
```html
<body>
<h1>Hello, {{ firstname }}</h1>
<input type="text" @keyup="updateFirstname" />
<script>
const _ = initFigue('body');
_.firstname = '';
_.updateFirstname = (event) => {
data.firstname = event.target.value;
};
</script>
</body>
```
As you can see, the `event` object is automatically passed as an argument to the event handler.
Figue supports any event type supported by the `addEventListener()` method, preceded by the `@` symbol.
## Next steps
Although being as simple and light as possible is a requirement for Figue, there is still lots of room for improvement and new functionalities.
- Adding Vue-style refs to quickly and easily reference HTML attributes instead of using `document.querySelector()`.
- Executing Javascript code within the template, using the `{{ ... }}` syntax.
- Adding conditional rendering and loops within the template.
- Rewriting the framework in Typescript. | An experimental frontend framework | framework,frontend,javascript | 2023-08-01T16:21:26Z | 2023-08-05T17:12:23Z | null | 1 | 0 | 27 | 0 | 0 | 6 | null | null | JavaScript |
ihshadin/flex-code | main | # [FlexCode - Unlock the Power of Problem Solving](https://flex-code-6541d.web.app/)
<p align="center">
<img src="./public/20230810_120154.png" alt="FlexCode Logo" width="250" height="250">
</p>
FlexCode is an online platform designed to host and manage coding challenges and problem-solving activities for coding enthusiasts, developers, and programmers. This README provides an overview of the project, its key features, technology stack, and how to get started.
## Table of Contents
1. [Overview](#overview)
2. [Key Features](#key-features)
3. [Unique Features](#unique-features)
4. [Technology Stack](#technology-stack)
5. [Project Structure](#project-structure)
6. [Development Plan](#development-plan)
7. [Potential Enhancements](#potential-enhancements)
8. [Creators](#creators)
9. [Conclusion](#conclusion)
## Overview
FlexCode is an online platform designed to host and manage coding challenges and problem-solving activities for coding enthusiasts, developers, and programmers. This platform provides a flexible and interactive environment where participants can showcase their coding skills and solve challenges. FlexCode is built using modern technologies, including React.js for the frontend, Express.js for the backend, Firebase for user authentication, MongoDB with Mongoose for contest data storage, and JWT for secure authentication.
## Key Features
- **User Authentication:** Secure user registration, login, and password reset using Firebase Authentication with JWT integration.
- **Challenge Management:** Admin users can create and manage coding challenges with input, output, and test case specifications.
- **User Dashboard:** Participants can access their user dashboard, view upcoming contests, participation history, and leaderboard rankings.
- **Real-time Submissions:** Participants can submit code solutions, and FlexCode will evaluate, score, and display real-time results.
- **Leaderboard:** The platform displays leaderboard rankings for each contest based on user performance.
- **Code Editor:** A feature-rich code editor with syntax highlighting for writing and submitting code solutions.
- **Blogs:** Users can read and explore programming-related articles.
- **User Counter:** Track the number of users visiting the website.
- **Problem of the Day:** Present a daily coding challenge on an individual section.
## Unique Features
- **Blogs:** Explore programming-related articles.
- **User Counter:** Track the number of users visiting the website.
- **Problem of the Day:** Daily coding challenges to engage users.
## Technology Stack
**Frontend:**
- React.js
- HTML
- CSS
- JavaScript
- Tailwind CSS
- Axios
**Backend:**
- Express.js
- Node.js
**Database:**
- MongoDB with Mongoose
**Authentication:**
- Firebase Authentication with JWT integration
**Code Evaluation:**
- Code Mirror environment for securely executing user-submitted code
**Hosting:**
- Deployment on a cloud platform like Firebase and Vercel
### Here are the main dependencies and devDependencies used in the project:
### Dependencies
| Package | Version |
| ----------------------------------------- | ---------- |
| `@emailjs/browser` | ^3.11.0 |
| `@tomickigrzegorz/react-circular-progress-bar` | ^1.1.2 |
| `aos` | ^2.3.4 |
| `framer-motion` | ^10.12.17 |
| `localforage` | ^1.10.0 |
| `match-sorter` | ^6.3.1 |
| `react` | ^18.2.0 |
| `react-dom` | ^18.2.0 |
| `react-icons` | ^4.9.0 |
| `react-router-dom` | ^6.13.0 |
| `react-tilt` | ^1.0.2 |
| `sort-by` | ^1.2.0 |
| `typed.js` | ^2.0.16 |
### Dev Dependencies
| Package | Version |
| ------------------------------------ | ---------- |
| `@types/react` | ^18.0.37 |
| `@types/react-dom` | ^18.0.11 |
| `@vitejs/plugin-react` | ^4.0.0 |
| `autoprefixer` | ^10.4.14 |
| `eslint` | ^8.38.0 |
| `eslint-plugin-react` | ^7.32.2 |
| `eslint-plugin-react-hooks` | ^4.6.0 |
| `eslint-plugin-react-refresh` | ^0.3.4 |
| `postcss` | ^8.4.24 |
| `tailwindcss` | ^3.3.2 |
| `vite` | ^4.3.9 |
## Project Structure
The project is organized into the following components:
- **Frontend Pages**: Home Page, Login, Signup, Dashboard, Contest Details, Code Editor
- **Components**: Navbar, Footer, Contest List, Contest Card, Leaderboard, Count Users, etc.
For user authentication and state management, refer to the optional section in the project structure.
## Development Plan
The development process can be divided into the following milestones:
1. Set up the project structure, create the React.js frontend, and integrate Firebase Authentication for user registration and login.
2. Implement user authentication using JWT, enabling access to specific routes based on user roles (admin, participant).
3. Set up MongoDB for storing contest data, including contest details, challenges, and user submissions.
4. Develop the problem-solving creation and challenge management functionality for admin users.
5. Implement the user dashboard, displaying upcoming problems, participation history, and leaderboard rankings.
6. Create the code editor component for users to write and submit code solutions.
7. Perform thorough testing and debugging of the entire application.
8. Deploy the application to a cloud platform for public access.
## Potential Enhancements
After completing the primary features, consider adding these enhancements:
- **Notifications:** Implement real-time notifications for contest updates and announcements.
- **Code Sharing:** Allow participants to share and discuss their solutions.
- **Code Review:** Introduce a code review feature for feedback on solutions.
## Creators
Meet the DevGenius team behind FlexCode:
- [Imam Hossain (Team Lead)](https://github.com/ihshadin)
- [Mehedi Hasan Foysal](https://github.com/mehedihasan8)
- [Abu Sayeed](https://github.com/studentabusayeed)
- [Omar Faruq](https://github.com/OmarFaruq967)
- [Jahid Hasan Zarif](https://github.com/Jahidmorol)
- [Nur Mohammad Chowdhury](https://github.com/nmcsakib)
## Conclusion
FlexCode is an exciting problem-solving website built with React.js, Firebase, MongoDB, Mongoose, JWT, and Express.js. The platform aims to provide a flexible and interactive environment for coding enthusiasts to participate in problem-solving challenges. Throughout the development process, prioritize user experience, data security, and scalability to deliver a robust and user-friendly platform. Happy coding!
| FlexCode is an online platform designed to host and manage problem-solving and coding challenges for coding enthusiasts, developers, and programmers. The platform aims to provide a flexible and interactive environment where participants can showcase their coding skills and solve challenges. FlexCode will be built using a modern tech stack, combinin | express,javascript,mongoose,nodejs,react | 2023-08-07T11:07:06Z | 2023-11-26T06:55:23Z | null | 6 | 248 | 657 | 0 | 1 | 6 | null | null | JavaScript |
kullna/editor | main | <p align="center"><a href="https://editor.kullna.org/"><img src="https://www.kullna.org/brand/logo.svg" width="150"></a></p>
<h1 align="center">@kullna/editor</h1>
<h3 align="center">A small but feature-rich code editor for the web</h3>
<p align="center"><img src="https://editor.kullna.org/assets/images/screenshot.png" style="image-rendering: pixelated;" width="698" alt="screenshot"></p>
<p align="center">
<a href="https://editor.kullna.org/demo.html">🔍 Demos</a> •
<a href="https://editor.kullna.org/modules.html">📖 Docs</a> •
<a href="https://editor.kullna.org/pages/CONTRIBUTING.html">🙌 Contribute</a>
</p>
<p align="center">
<a href="https://github.com/kullna/editor">
<img src="https://img.shields.io/badge/GitHub-Open_Source-d33682" alt="@kullna/editor on GitHub">
</a>
</p>
<p align="center">
<a href="https://cdn.jsdelivr.net/npm/@kullna/editor/dist/kullna-editor.min.js">
<img src="https://img.shields.io/badge/CDN-JSDelivr-2aa198" alt="CDN">
</a>
<a href="https://www.npmjs.com/package/@kullna/editor">
<img src="https://img.shields.io/npm/v/@kullna/editor?color=dc322f" alt="npm">
</a>
<img src="https://deno.bundlejs.com/?q=@kullna/editor&badge=small" alt="npm bundle size">
<a href="https://www.gnu.org/licenses/lgpl-3.0">
<img src="https://img.shields.io/badge/License-LGPL_v3-b58900.svg" alt="License: LGPL v3">
</a>
<a href="https://www.codefactor.io/repository/github/kullna/editor">
<img src="https://www.codefactor.io/repository/github/kullna/editor/badge" alt="CodeFactor">
</a>
<a href="https://discord.kullna.org/">
<img src="https://img.shields.io/badge/Join-Discord-6c71c4" alt="Join us on Discord">
</a>
</p>
<p><br/></p>
`@kullna/editor` is a browser-based code editor component developed and maintained by
[The Kullna Programming Language Project](http://www.kullna.org/).
As we were working on the Kullna IDE, we found the need for a reliable `contenteditable` code
editing surface with features like syntax highlighting, indentation management, line highlighting,
and a customizable gutter for adding breakpoints and bookmarks. For us, an essential requirement was
support for Right-to-Left (RTL) languages too.
Most of the existing editors were either too heavy and didn't work with RTL, or too simple and
didn't include sufficient features for our needs. We wanted a simple yet versatile editor that we
could easily extend to meet our specific needs, and which didn't break foundational features like
RTL support in the process. One that, if we needed to, we could maintain ourselves.
To address this gap, we're introducing `@kullna/editor`. A simple yet versatile code editor,
designed with extensibility in mind and built-in RTL support. If you're looking for a lightweight
code editor for your web application, we hope you'll find `@kullna/editor` useful, and we welcome
your feedback and contributions.
## Features
- 🎨 **Syntax Highlighting**: Integrate with Highlight.JS, Prism, or design your custom solution.
- ⏪ **Undo/Redo**: Offers customizable undo/redo levels.
- ✂️ **Copy-Paste**: Ensure consistent cross-browser cut, copy, and paste operations in an
XSS-secure way.
- 🎁 **Wrapping**: Wrap text, and keep line numbers and highlights in sync.
- 🖊️ **Bracket Management**: Automatic close-bracket and close-quote insertion, with type-over
capability.
- ➡️ **Code Indentation**: Flexible code indentation using tab or shift-tab. Supports multi-line
selections.
- 🧐 **Active Line Highlighting**: Spotlight the active line or indicate the debugger's current
execution point.
- 🔧 **Customizable Gutter**: Define your gutter contents like breakpoint or bookmark labels while
benefiting from our rendering strategies.
- 🖱️ **Input Processors**: Intuitive APIs designed to allow you to extend the input processing logic
to meet your needs.
- 🌍 **Full RTL Support**: Dedicated support for right-to-left languages.
## Why @kullna/editor?
- 🎯 **Just Right**: Striking a balance between simplicity and flexibility.
- 🌐 **Modern APIs**: No more browser compatibility headaches.
- 📚 **Flexibility**: Integrate auto-complete, inline help, or other custom input event logic.
- 🚀 **Active Maintenance**: Continuously developed for the Kullna IDE.
- 💪 **RTL & I18N**: Comprehensive support without compromise.
- 👥 **Join Us**: We're open to contributions!
## Contribute
We envision a community-driven evolution for `@kullna/editor`. Your feedback, ideas, and
contributions can shape the future of this editor, making it even more versatile and user-friendly.
If our vision resonates with yours, consider contributing.
👉 [Read the Contributing Page](https://editor.kullna.org/pages/CONTRIBUTING.html) for more details.
---
The Kullna Editor source, artifacts, and website content are **Copyright (c) 2023
[The Kullna Programming Language Project](https://www.kullna.org/).**
They are free to use and open-source under the terms of the
[GNU Lesser General Public License](https://www.gnu.org/licenses/lgpl-3.0).
| A small but feature-rich code editor for the web | code-editor,javascript,line-numbers,rtl,syntax-highlighting,breakpoints,contenteditable,typescript,code,editor | 2023-08-03T14:01:19Z | 2023-08-29T21:53:10Z | 2023-08-29T21:53:10Z | 1 | 26 | 160 | 5 | 1 | 6 | null | NOASSERTION | TypeScript |
ngoworldcommunity/NGOWorld-Backend | main | [](https://opensource.org/licenses/MIT) [](https://github.com/MilanCommunity/Milan-Backend/releases) 
# What is Milan ?
Milan is a hub to **connect** NGOs, Charities, and the world to **collaborate** and **build** a better tomorrow. Sign up as an organization/user and be a cause for change. Don't forget to drop a star ⭐.
<br/>
<div align="center" >
<div align="center" >
<a href="https://api.ngoworld.org/"><img alt="C" src="https://img.shields.io/badge/Production%20Release-07C160?style=for-the-badge&logo=vercel&logoColor=white"></a> <a href="https://github.com/sponsors/tamalCodes"><img alt="Sponsor Tamal" src="https://img.shields.io/badge/sponsor-30363D?style=for-the-badge&logo=GitHub-Sponsors&logoColor=#white"></a>
</div>
<img alt="Milan Readme Banner" src="./docs/pictures/MilanBanner.png" width="700px"/>
</div>
<br>
# Tech Stack(Backend) 💻
<p >
<a href="https://nodejs.org/it/docs"><img alt="C" src="https://img.shields.io/badge/node.js-%2343853D.svg?style=for-the-badge&logo=node.js&logoColor=white"></a>
<a href="https://expressjs.com/"><img alt="C" src="https://img.shields.io/badge/express.js-%23404d59.svg?style=for-the-badge"></a>
<a href="https://www.mongodb.com/docs/"><img alt="C" src="https://img.shields.io/badge/MongoDB-%234ea94b.svg?style=for-the-badge&logo=mongodb&logoColor=white"></a>
<a href="https://docs.github.com/en"><img alt="C" src="https://img.shields.io/badge/GitHub-%23121011.svg?style=for-the-badge&logo=github&logoColor=white"></a>
<a href="https://opensource.guide/how-to-contribute/"><img alt="C" src="https://img.shields.io/badge/Open%20Source-%23F05032.svg?style=for-the-badge&logo=open-source-initiative&logoColor=white"></a>
<a href="https://docs.github.com/en/actions"><img alt="C" src="https://img.shields.io/badge/GitHub%20Actions-%232671E5.svg?style=for-the-badge&logo=github-actions&logoColor=white"></a>
<a href="https://docs.github.com/en/actions"><img alt="C" src="https://img.shields.io/badge/Razorpay-02042B?style=for-the-badge&logo=razorpay&logoColor=3395FF"></a>
</p>
</br>
# Contributing to Milan 🔐
Remember, Good PR makes you a Good contributor !
We at Milan work hard to maintain the structure, and use conventional Pull request titles and commits. Without a proper template for the PR, not following the guidelines and spam might get the pull request closed, or banned.
## 1. Setting up the project locally
- [Forking + Cloning Guide](/docs/CloneSetup.md)
- [Setting up the Backend (current repo)](/docs/BackendSetup.md)
- [Setting up the Frontend](https://github.com/MilanCommunity/Milan/blob/main/docs/FrontendSetup.md)
- [Setting up with docker](/docs/DockerSetup.md)
## 2. Contributing guidelines & More
- [Proper API documentation](https://milan-server.onrender.com/docs/) for developers.
- [Contributing Guidelines](/CONTRIBUTING.md) to be followed.
# License 👮
Milan is Licensed under the <a href="./LICENSE">MIT License</a>. Please go through the License at least once before contributing.
# Support 🙏
**Don't forget to drop a star ⭐.** A heartfelt thank you to those who have contributed to this project. We are really grateful for your contribution. You all are amazing. Opensource for the win 🚀
| This is the official repository for Milan's server side codes. | backend,expressjs,hacktoberfest,javascript,mongodb,nodejs,opensource,swr,jwoc | 2023-08-08T16:48:21Z | 2024-04-16T16:59:01Z | 2023-08-08T22:07:33Z | 21 | 45 | 87 | 3 | 27 | 6 | null | MIT | JavaScript |
jsonfm/flask-image-bgremover | master | <img
src="./docs/images/preview.png"
/>
### 🌌 BgRemover
An image background remover application made with Python/Flask as a backend and HTML/JS/CSS as frontend. It's a full responsive website, designed with mobile first methodology.
The `API` endpoint is accessible in the `/removebg` path, which can be used as follows:
```js
const body = {
image: "some-image-on-base64-format",
};
try {
const response = await axios.post("/removebg", body);
const result = response?.data?.result;
} catch (error) {
console.error(error);
}
```
### ⚙️ Technologies
- Flask
- Pillow
- Rembg
- HTML/CSS/JS
- Alpine.js
### 📦 Installation
```
pip install -r requirements.txt
```
### ⚡️ Development
```
flask --app main run --debug
```
| 🌌 🌶️ An image background remover app made with Python Flask. | alpinejs,backend,background-remover,flask,image,pillow,python,css,html,javascript | 2023-08-06T17:56:12Z | 2023-08-06T22:25:01Z | null | 1 | 0 | 8 | 1 | 1 | 6 | null | null | HTML |
bkglobal/vercel-fastify-deploy-serverless | main | # Fastify API with Vercel Deployement Configuration.
Fastify api deployment on vercel using serverless. #fastify #serverless #vercel #deployement
GitHub template for a Fastify + Node + Typescript app that deploys to Vercel!
| Fastify api deployment on vercel using serverless. #fastify #serverless #vercel #deployement | api,deployment,fastify,fastifyjs,javascript,nodejs,serverless,serverless-function,vercel,vercel-serverless | 2023-08-03T08:38:21Z | 2023-08-03T10:07:36Z | null | 1 | 0 | 7 | 0 | 5 | 6 | null | null | TypeScript |
anupammallick88/OneTelemedicine | my-new-branch | ## One Telemedicine System
An One Telemedicine system is a technological solution designed to monitor and manage the health and well-being of patients from a distance. It leverages digital tools, devices, and communication technologies to collect and transmit relevant health data, allowing healthcare providers to remotely monitor and assess a patient's condition, provide timely interventions, and offer personalized care without requiring the patient to be physically present at a medical facility.
## About This Project
This project is a Telemedicine site built by bootstrap and Laravel 8.1.5.
There are some issues till now but I will fix it and make more perfectly.
## About developer
This project was built by full-stack web developer named Anupam mallick.
I come from India and was born in 02.03.1988.
I live in Kolkata now and you can find me in anytime.
Please contact me via anup88.2010@gmail.com
## About Laravel
Laravel is a web application framework with expressive, elegant syntax. We believe development must be an enjoyable and creative experience to be truly fulfilling. Laravel takes the pain out of development by easing common tasks used in many web projects, such as:
- [Simple, fast routing engine](https://laravel.com/docs/routing).
- [Powerful dependency injection container](https://laravel.com/docs/container).
- Multiple back-ends for [session](https://laravel.com/docs/session) and [cache](https://laravel.com/docs/cache) storage.
- Expressive, intuitive [database ORM](https://laravel.com/docs/eloquent).
- Database agnostic [schema migrations](https://laravel.com/docs/migrations).
- [Robust background job processing](https://laravel.com/docs/queues).
- [Real-time event broadcasting](https://laravel.com/docs/broadcasting).
Laravel is accessible, powerful, and provides tools required for large, robust applications.
## Learning Laravel
Laravel has the most extensive and thorough [documentation](https://laravel.com/docs) and video tutorial library of all modern web application frameworks, making it a breeze to get started with the framework.
If you don't feel like reading, [Laracasts](https://laracasts.com) can help. Laracasts contains over 1500 video tutorials on a range of topics including Laravel, modern PHP, unit testing, and JavaScript. Boost your skills by digging into our comprehensive video library.
## Laravel Sponsors
We would like to extend our thanks to the following sponsors for funding Laravel development. If you are interested in becoming a sponsor, please visit the Laravel [Patreon page](https://patreon.com/taylorotwell).
- **[Vehikl](https://vehikl.com/)**
- **[Tighten Co.](https://tighten.co)**
- **[Kirschbaum Development Group](https://kirschbaumdevelopment.com)**
- **[64 Robots](https://64robots.com)**
- **[Cubet Techno Labs](https://cubettech.com)**
- **[Cyber-Duck](https://cyber-duck.co.uk)**
- **[British Software Development](https://www.britishsoftware.co)**
- **[Webdock, Fast VPS Hosting](https://www.webdock.io/en)**
- **[DevSquad](https://devsquad.com)**
- [UserInsights](https://userinsights.com)
- [Fragrantica](https://www.fragrantica.com)
- [SOFTonSOFA](https://softonsofa.com/)
- [User10](https://user10.com)
- [Soumettre.fr](https://soumettre.fr/)
- [CodeBrisk](https://codebrisk.com)
- [1Forge](https://1forge.com)
- [TECPRESSO](https://tecpresso.co.jp/)
- [Runtime Converter](http://runtimeconverter.com/)
- [WebL'Agence](https://weblagence.com/)
- [Invoice Ninja](https://www.invoiceninja.com)
- [iMi digital](https://www.imi-digital.de/)
- [Earthlink](https://www.earthlink.ro/)
- [Steadfast Collective](https://steadfastcollective.com/)
- [We Are The Robots Inc.](https://watr.mx/)
- [Understand.io](https://www.understand.io/)
- [Abdel Elrafa](https://abdelelrafa.com)
- [Hyper Host](https://hyper.host)
- [Appoly](https://www.appoly.co.uk)
- [OP.GG](https://op.gg)
## Contributing
Thank you for considering contributing to the Laravel framework! The contribution guide can be found in the [Laravel documentation](https://laravel.com/docs/contributions).
## Code of Conduct
In order to ensure that the Laravel community is welcoming to all, please review and abide by the [Code of Conduct](https://laravel.com/docs/contributions#code-of-conduct).
## Security Vulnerabilities
If you discover a security vulnerability within Laravel, please send an e-mail to Taylor Otwell via [taylor@laravel.com](mailto:taylor@laravel.com). All security vulnerabilities will be promptly addressed.
## License
The Laravel framework is open-sourced software licensed under the [MIT license](https://opensource.org/licenses/MIT).
# OneTelemedicine
| An One Telemedicine system is a technological solution designed to monitor and manage the health and well-being of patients from a distance. | blade-template,doctor-appointment-management,fullstack-development,javascript,laravel,mysql,php,telemedicine,vue,telemedicine-project | 2023-08-08T05:40:47Z | 2023-08-08T05:43:44Z | null | 1 | 0 | 1 | 0 | 4 | 6 | null | null | JavaScript |
vikrammahto/tototimer | master | # Tototimer - PWA App to Manage Time, Money and Work
Tototimer is your all-in-one solution for efficient time management, productivity, and organization. Built using React JS and Tailwind CSS.
## Features
- Pomodoro timer
- Task Manger [Todo List]
- Live Weather Forecast
- Upcoming features: Notes, Income/Expense Tracker
## Developemnt
This project was bootstrapped with [Create React App](https://github.com/facebook/create-react-app).
```shell
git clone https://github.com/vikrammahto/tototimer.git
```
```shell
cd tototimer
```
```shell
npm install
```
```shell
npm start
```
## Contribution
To contribute on this project follow below steps.
PS: Create an issue before start working
1. Fork it
2. Create your a new branch
3. Commit your changes
4. Push to the branch
5. Create a new Pull Request
## Credits
Image: Pixabay | [5187396](https://pixabay.com/illustrations/horse-man-desert-rider-person-2255876/), [Patricia_Roman](https://pixabay.com/illustrations/landscape-deer-mountain-nature-5426755/), [kskr123pak](https://pixabay.com/illustrations/sea-sunset-boat-nature-ocean-sky-7331682/)
Icons: [Tabler Icons](https://tabler-icons.io/)
Weather API: [OpenWeatherMap](https://openweathermap.org/api)
## License
This project is open source and available under the MIT License. | Tototimer is your all-in-one solution for efficient time management, productivity, and organization. Built using React JS and Tailwind CSS. | javascript,pomodoro,pomodoro-timer,productivity,react,tailwindcss,todolist,weather-app | 2023-08-06T04:17:44Z | 2023-08-21T11:32:11Z | null | 2 | 2 | 36 | 0 | 1 | 6 | null | MIT | JavaScript |
apoorvapendse/CruSyt | main | # CruSyt
Decode Social Buzz, Drive Informed Decisions through Crucial Insights using Sentiment Analysis.
## Tech Stack:
- Express MVC
- mongoose
- firebase for auth
- cheerio for scraping reddit top comments
- natural for SA
- CSS and vanila js for frontend
#### The Project is used to determine the social media value of brands/ businesses / individuals among internet users employing express, nodejs for the server
#### The data is fetched is using apis or by scraping the platforms depending on the availability of data
### If you are interested in contributing, check out the CONTRIBUTING.md file
You can also contact [Apoorva Pendse](https://github.com/apoorvapendse) for queries related to the project.
| Decode Social Buzz, Drive Informed Decisions through Crucial Insights using Sentiment Analysis. | css,express,firebase,hacktoberfest,html,javascript,natural-language-processing,nodejs,ejs,express-mvc | 2023-08-06T09:07:41Z | 2023-11-25T04:59:17Z | null | 7 | 8 | 84 | 4 | 6 | 6 | null | null | CSS |
Bayu-x3/BotWea.v1 | main | <h1 align="center">Voldigoad WhatsApp - Ai
</h1>
<p align="center">
<img src="https://i.ibb.co/P95BCqP/Colorful-Artificial-Intelligence-Logo.jpg" width="128" height="128"/>
</p>
<p align="center">
<a href="#"><img title="Whatsapp-Bot" src="https://img.shields.io/badge/Whatsapp Bot-green?colorA=%23ff0000&colorB=%23017e40&style=for-the-badge"></a>
</p>
<p align="center">
<a href="https://github.com/Bayu-x3"><img title="Author" src="https://img.shields.io/badge/Author-Bayux3-red.svg?style=for-the-badge&logo=github"></a>
</p>
<p align="center">
<a href="https://github.com/Bayu-x3/followers"><img title="Followers" src="https://img.shields.io/github/followers/bayu-x3?color=blue&style=flat-square"></a>
<a href="https://github.com/Bayu-x3/BotWea.v1/stargazers/"><img title="Stars" src="https://img.shields.io/github/stars/Bayu-x3/BotWea.v1?color=red&style=flat-square"></a>
<a href="https://github.com/Bayu-x3/BotWea.v1/watchers"><img title="Watching" src="https://img.shields.io/github/watchers/Bayu-x3/BotWea.v1?label=Watchers&color=blue&style=flat-square"></a>
<a href="#"><img title="UNMAINTENED" src="https://img.shields.io/badge/UNMAINTENED-YES-blue.svg"</a>
</p>
## Clone this project
```bash
> https://github.com/Bayu-x3/BotWea.v1
```
## Install the dependencies:
Before running the below command, make sure you're in the project directory that
you've just cloned!!
```bash
> npm install
```
### Usage
Before running this script, first edit [this section](https://github.com/Bayu-x3/BotWea.v1/blob/main/index.js#L8) with your Chrome Path
```bash
> npm start
```
## Features
| Category | Feature |
| -------------- | ----------------------------------------- |
| Downloader | YoutubeMp3 Download |
| | YoutubeMp4 Download |
| | FacebookVideo Download |
| | InstagramVideo Download |
| | TiktokVideo Download (No Wm) |
| | TwitterVideo Download |
| | Mediafire Download |
| | SoundCloud - Download |
| Text To Speech | Bahasa Indonesia |
| | Bahasa Inggris |
| | Bahasa Jepang |
| | Bahasa Prancis |
| | Bahasa Thailand |
| | Bahasa Russia |
| Stalker | Instagram Stalking |
| | Github Stalking |
| | Tiktok Stalking |
| URL Shortener | ShortUrl Menggunakan bitly |
| | ShortUrl Menggunakan cutly |
| | ShortUrl Menggunakan tinurl |
| | ShortUrl Menggunakan shrt |
| Generator | QrCode Generator |
| | Brainfuck Generator |
| | Hash Generator |
| | Fakedata generator |
| Check E-Wallet | Check Ovo |
| | Check Gopay |
| | Check LinkAja |
| | Check ShopeePay |
| Network Tools | ScanCms |
| | Clickjacking test |
| | Reverse IP |
| | WhoisLookup |
| Other | ChatGpt |
| | SimSimi |
| | LirikLagu |
| | ChordLagu |
| | Wikipedia |
| | Check KodePos |
| Bot WhatsApp bernama Voldigoad Ai yang memiliki banyak fitur fitur | ai,artificial-intelligence,bot,botwhatapp-md,botwhatsapp,wabot,javascript,rest-api,restful-api,whatsapp-web | 2023-07-28T10:39:36Z | 2023-07-28T16:50:21Z | null | 1 | 0 | 16 | 0 | 0 | 6 | null | null | JavaScript |
DevRohit06/blog | main |
# DevBlogs - A Blogging Website
## Introduction
Welcome to Bloggling - a modern and elegant blogging website built using [Astro](https://astro.build) and [Tailwind CSS](https://tailwindcss.com). Bloggling offers a seamless experience for both bloggers and readers, with its intuitive user interface and responsive design. Whether you're a seasoned blogger or just starting your writing journey, Bloggling provides an ideal platform to share your thoughts with the world.
## Features
- **Fast and Efficient:** Bloggling leverages Astro's static site generation to ensure lightning-fast loading times and optimal performance.
- **Beautiful Design:** The website's design is powered by Tailwind CSS, offering a visually appealing and responsive layout across all devices.
- **User-Friendly Interface:** With a clean and intuitive user interface, Bloggling makes writing and managing blog posts a breeze.
- **Categories and Tags:** Organize your blog posts using categories and tags to help readers discover content relevant to their interests.
- **SEO Friendly:** Bloggling is designed with SEO best practices in mind, ensuring your blog posts rank well in search engines.
## Getting Started
To run Bloggling locally and start writing your blogs, follow these steps:
1. Clone the repository:
```
https://github.com/DevRohit06/blog.git
```
2. Navigate to the project directory:
```
cd blog
```
3. Install dependencies:
```
yarn install or npm install
```
4. Start the development server:
```
npm run dev or yarn run dev
```
This will launch the website on `http://localhost:3000` by default.
## Writing Blog Posts
To write a new blog post, follow these steps:
1. Create a new `.md` file in the `src/posts` directory with your blog content. You can use Markdown syntax for formatting.
2. Add frontmatter at the top of the file to specify the title, date, category, and tags of your blog post:
```md
---
title: My Awesome Blog Post
date: 2023-08-01
description: This is description
ogImagePath: hero image
tags: [Programming, Web Development]
---
```
3. Save the file, and the website will automatically generate the new blog post.
## Deployment
To deploy Bloggling to a static hosting service, run the following command:
```
npm run build or yarn run build
```
This will create a `build` directory containing the static assets ready for deployment.
## Contributing
We welcome contributions to make Bloggling even better! If you find a bug or have an idea for improvement, feel free to open an issue or submit a pull request on [GitHub](https://github.com/yDevRohit06/blog).
## License
Blog is open-source and released under the [MIT License](https://opensource.org/licenses/MIT).
---
We hope you enjoy using Bloggling to create and share captivating blog posts. Happy blogging!
[Live Demo](https://blog-trohit06.vercel.app) | [GitHub Repository](https://github.com/DevRohit06/blog.git)
| A Blogging website made using Astro and Tailwind css | astro,astrojs,astrojs-blog,blog,blog-website,javascript,tailwindcss,typescript,trending | 2023-08-02T19:30:13Z | 2023-08-23T16:36:05Z | null | 2 | 1 | 79 | 0 | 0 | 6 | null | MIT | Astro |
react18-tools/esbuild-react18-useclient | main | # esbuild-react18-useclient [](https://www.npmjs.com/package/esbuild-react18-useclient) [](https://www.npmjs.com/package/esbuild-react18-useclient) [](https://github.com/mayank1513/esbuild-react18-useclient/actions/workflows/publish-to-npm-on-new-release.yml)
> This package is deprecated in favor of [esbuild-plugin-react18](https://github.com/mayank1513/esbuild-plugin-react18)
> Please switch to [esbuild-plugin-react18](https://github.com/mayank1513/esbuild-plugin-react18), which also offers additional options and more control over your build output.
<img src="https://github.com/mayank1513/esbuild-react18-useclient/blob/main/esbuild-react18.jpg?raw=true" title="Build Awesome Libraries using React Server Components and make your Mark!" style="width:100%"/>
> Build Awesome Libraries using React Server Components and make your Mark!
This is an `esbuild` plugin for compiling libraries compatible with React 18 server and client component, Nextjs13, Remix, etc.
## Why?
✅ Unleash the power of combining react client and server components in your libraries
✅ Full TypeScript support out of the box
✅ Simple and tiny
✅ Easy to use — just add the plugin, and you are good to go
Introduction of React server components in React 18 has unlocked immense possibilities. However, library authors are not yet able to fully encash upon this potential. Many libraries, like `chakra-ui`, simply add “use client” for each component. However, much more can be unleashed when we can use both server and client components to build libraries. Also check-out this [blog](https://mayank1513.medium.com/unleash-the-power-of-react-server-components-eb3fe7201231).
## Example
Checkout https://github.com/mayank1513/nextjs-themes
## Compatibility
- JavaScript/TypeScript React libraries using `tsup` or other builders based on `esbuild`
This plugin seamlessly integrates with `tsup` and any other builders based on `esbuild`. With this you can have both server and client components in your library and the plugin will take care of the rest. All you need to do is add this plugin and add `"use client";` on top of client components (in your source code).
## Add dependencies:
```bash
yarn add --dev esbuild-react18-useclient
```
or
```bash
pnpm add -D esbuild-react18-useclient
```
or
```bash
npm install -D esbuild-react18-useclient
```
> If you are using `monorepo` or `workspaces` you can install this plugin to root using `-w` or to specific workspace using `--filter your-package` or `--scope your-package` for `pnpm` and `yarn` workspaces respectively.
## Use with `tsup`
```javascript
// tsup.config.ts or tsup.config.js
import { defineConfig } from "tsup";
import reactUseClient from "esbuild-react18-useclient";
export default defineConfig(options => ({
...
esbuildPlugins:[reactUseClient]
}));
```
## License
Licensed as MIT open source.
<hr />
<p align="center" style="text-align:center">with 💖 by <a href="https://mayank-chaudhari.vercel.app" target="_blank">Mayank Kumar Chaudhari</a></p>
| esbuild plugin for compiling libraries compatible with React 18 server and client component, Nextjs13, Remix, etc. Please use Turborepo Template -> https://github.com/react18-tools/turborepo-template | esbuild,esbuild-plugin,javascript,nextjs,nodejs,react-libraries,react-server-components,react18,reactjs,tsup | 2023-07-31T10:30:17Z | 2023-09-30T16:51:22Z | 2023-09-30T16:48:08Z | 1 | 4 | 24 | 1 | 0 | 6 | null | MIT | TypeScript |
PabloBona/space-travelers | develop | <a name="readme-top"></a>
<div align="center">
<img src="./src/assets/images/planet.png" alt="logo" width="140" height="auto" />
</div>
<!-- TABLE OF CONTENTS -->
# 📗 Table of Contents Space Travelers
- [📗 Table of Contents](#-table-of-contents)
- [📖 Space-Travelers](#space-travelers)
- [🛠 Built With ](#-built-with-)
- [Tech Stack ](#tech-stack-)
- [Key Features ](#key-features-)
- [🚀 Live Demo ](#-live-demo-)
- [💻 Getting Started ](#getting-started)
- [Install](#-install)
- [Usage](#-usage)
- [Run tests](#run-tests)
- [Deployment](#deployment)
- [👥 Authors ](#-author-)
- [🔭 Future Features ](#-future-features-)
- [🤝 Contributing ](#-contributing-)
- [⭐️ Show your support ](#️-show-your-support-)
- [🙏 Acknowledgments ](#-acknowledgments-)
- [❓ FAQ (OPTIONAL) ](#-faq-optional-)
- [📝 License ](#-license-)
<!-- PROJECT DESCRIPTION -->
<br>
# 📖 Space-travelers (space-travelers) <a name="space-travelers"></a>
In this project, we have built a web application for a company that provides commercial and scientific space travel services. The application allows users to book rockets and join selected space missions using real live data from the SpaceX API.
# How it Works
The Space Travelers' Hub consists of three main sections:
# Rockets / Dragons
The Rockets section displays a list of all available SpaceX rockets. Users can easily book each rocket by clicking the reservation button or cancel their previously made booking. If your team has three members, the Dragons section is also included with the same functionalities.
# Missions
In the Missions section, users can explore and join different space missions. The application fetches real-time data from the SpaceX API to provide accurate information about upcoming missions.
# My Profile
The My Profile section allows users to view their booking history and the missions they have joined. Users can also manage their profile settings and make changes as needed.
<br>
<p align="right">(<a href="#readme-top">back to top</a>)</p>
## 🛠 Built With <a name="built-with"></a>
### Tech Stack <a name="tech-stack"></a>
The following stacks were used
<details style="color:rgb(87, 247, 255);">
<ul>
<li><a href="https://developer.mozilla.org/en-US/docs/Web/HTML">HTML</a></li>
<li><a href="https://developer.mozilla.org/en-US/docs/Web/CSS">CSS</a></li>
<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript">Javascript</a></li>
<li><a href="hhttps://create-react-app.dev/">Create React App</a></li>
</ul>
</details>
<!-- Features -->
<p align="right">(<a href="#readme-top">back to top</a>)</p>
### Key Features <a name="key-features"></a>
- **ReactJS library**
- **Using JSX syntax**
- **Unit test with jest**
- **Boostrap**
<p align="right">(<a href="#readme-top">back to top</a>)</p>
### 🚀 Live Demo <a name="live-demo"></a>
<a href="https://spacextravels.netlify.app/">Live Demo</a>
<!-- GETTING STARTED -->
<br>
# 💻 Getting Started <a name="getting-started"></a>
Clone this repository to your desired folder:
Example commands:
```bash
git clone git@github.com:PabloBona/space-travelers.git
```
<br>
# 📖 Install
Install this project's dependencies with:
```
cd space-travelers
npm install
```
<br>
# 📖 Usage
To run the project, execute the following command:
```bash
npm run start
```
Runs the app in the development mode.\
Open [http://localhost:3000](http://localhost:3000) to view it in your browser.
The page will reload when you make changes.\
You may also see any lint errors in the console.
<br>
# Run tests
```bash
npm test
```
<br>
# 📖 Run linterns tests
If you follow the tutorial above to setup linters then you can run these tests
```$
npx hint .
```
```$
npx stylelint "**/*.scss"
```
or if you use css then run this instead of the latter command above
```$
npx stylelint "**/*.{css,scss}"
```
<br>
# Available Scripts
In the project directory, you can run:
### `npm run eject`
**Note: this is a one-way operation. Once you `eject`, you can't go back!**
### Deployment
You can deploy this project using: GitHub Pages or Netlify
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- AUTHORS -->
### 👥 Author <a name="authors"></a>
- 👤 **Pablo Bonasera** - GitHub: [@BonPa](https://github.com/PabloBona)
- 👤 **Hajnalka Oltyan** - GitHub: [@Hajnalka](https://github.com/hajnaloltyan)
- 👤 **Ali Baba** - GitHub: [@Ali Baba](https://github.com/Alibaba2023)
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- FUTURE FEATURES -->
## 🔭 Future Features <a name="future-features"></a>
- [ ] **Customizable notifications and alerts**
- [ ] **Multilingual support**
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- CONTRIBUTING -->
## 🤝 Contributing <a name="contributing"></a>
Contributions, issues, and feature requests are welcome!
Feel free to check the [issues page](https://github.com/PabloBona/space-travelers/issues).
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- SUPPORT -->
## ⭐️ Show your support <a name="support"></a>
If you like this project you can follow me on github for more.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- ACKNOWLEDGEMENTS -->
## 🙏 Acknowledgments <a name="acknowledgements"></a>
- We would like to express our heartfelt gratitude to Microvere for the invaluable learning experience they have provided. The supportive community, dedicated mentors, and remote collaboration opportunities have enhanced my technical skills and prepared me for real-world projects.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- FAQ (optional) -->
## ❓ FAQ (OPTIONAL) <a name="faq"></a>
- **Are the linters necessary?**
- It is a good practice to install and use them as they guide you towards best practice, but yes you can do without.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- LICENSE -->
## 📝 License <a name="license"></a>
This project is [MIT](https://github.com/PabloBona/space-travelers/blob/live-demo/MIT.md) licensed.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
| In this task, we will be working with the real live data from the SpaceX API. Our task is to build a web application for a company that provides commercial and scientific space travel services. The application will allow users to book rockets and join selected space missions. | design,javascript,react,redux-toolkit | 2023-07-23T13:34:18Z | 2023-11-20T11:20:34Z | null | 3 | 22 | 84 | 0 | 2 | 6 | null | null | JavaScript |
MozamelJawad/Leaderboard | development | # Leaderboard
<a name="readme-top"></a>
<!-- TABLE OF CONTENTS -->
# 📗 Table of Contents
- [📖 About the Project](#about-project)
- [🛠 Built With](#built-with)
- [Tech Stack](#tech-stack)
- [Live Demo](#live-demo)
- [Key Features](#key-features)
- [💻 Getting Started](#getting-started)
- [Setup](#setup)
- [Prerequisites](#prerequisites)
- [Install](#install)
- [Usage](#usage)
- [Run tests](#run-tests)
- [Deployment](#deployment)
- [👥 Authors](#authors)
- [🔭 Future Features](#future-features)
- [🤝 Contributing](#contributing)
- [⭐️ Show your support](#support)
- [🙏 Acknowledgements](#acknowledgements)
- [📝 License](#license)
<!-- PROJECT DESCRIPTION -->
# 📖 Leaderboard <a name="about-project"></a>
**Leaderboard** is a learning project in Microverse that builds in HTML, CSS, and Javascript and uses webpack to bundle Javascript; in this project, proper ES6 syntax is also implemented.
## 🛠 Built With <a name="built-with"></a>
### Tech Stack <a name="tech-stack"></a>
<ul>
<li>Linters</li>
<li>Webpack</li>
<li>HTML</li>
<li>CSS3</li>
<li>JS (ES6 synthax)</li>
</ul>
## 🚀 Live Demo <a name="live-demo"></a>
- [Live Demo](https://mozameljawad.github.io/Leaderboard/dist/)
##
<!-- Features -->
### Key Features <a name="key-features"></a>
- **linter implementation**
- **webpack implementation**
- **ES6 Module**
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- GETTING STARTED -->
## 💻 Getting Started <a name="getting-started"></a>
### Setup
Clone this repository to your desired folder:
https://github.com/MozamelJawad/Leaderboard
### Install
<ul>
<li>npm init -y </li>
<li>npm install webpack webpack-cli --save-dev</li>
<li>npm install --save-dev html-webpack-plugin</li>
<li>npm install webpack webpack-cli --save-dev</li>
<li>npm install --save-dev style-loader css-loader </li>
<li>npm install --save-dev webpack-dev-server</li>
<li>npm run build</li>
<li>npm start </li>
</ul>
### Usage
To run the project, execute the following command:
> npm install
### Run tests
> np start
### Deployment
Project can be deployed by using the gh-pages and other web platforms.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- AUTHORS -->
## 👥 Authors <a name="authors"></a>
👤 **Mozamel Jawad**
- GitHub: [@githubhandle](https://github.com/MozamelJawad)
- Twitter: [@twitterhandle](https://twitter.com/mozameljawad)
- LinkedIn: [LinkedIn](https://www.linkedin.com/in/mozamel-jawad-2b4421111/)
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- FUTURE FEATURES -->
## 🔭 Future Features <a name="future-features"></a>
- [ ] **[I will try to add some more user interactivity using JS]**
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- CONTRIBUTING -->
## 🤝 Contributing <a name="contributing"></a>
Contributions, issues, and feature requests are welcome!
Feel free to check the [issues page](https://github.com/MozamelJawad/Leaderboard/issues).
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- SUPPORT -->
## ⭐️ Show your support <a name="support"></a>
If you like this project, give a ⭐️
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- ACKNOWLEDGEMENTS -->
## 🙏 Acknowledgments <a name="acknowledgements"></a>
I would like to thank from Microverse
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- LICENSE -->
## 📝 License <a name="license"></a>
This project is [MIT](./LICENSE) licensed.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
| This is a learning project on Microverse designed in HTML, CSS, and ES6 modules. In this project, we use webpack to bundle JavaScript. | css,es6-modules,html,javascript,linter-config,webpack5 | 2023-08-02T08:58:28Z | 2023-08-04T18:10:05Z | null | 1 | 4 | 31 | 0 | 0 | 6 | null | MIT | JavaScript |
gilda-prv/Word-Guessing-Game | main | # Word-Guessing-Game
### gameplay
Guess the Word is a game based on hang man game built using HTML, CSS, and JavaScript in english and persian language. The game challenges players to guess a word by suggesting letters, one at a time. Each correct letter guessed is revealed in the word, while incorrect guesses accumulate towards a maximum allowed limit. The game provides players with a fun and educational way to expand their vocabulary and improve their word-guessing skills.
### How to Play
1. When you start the game, a random word will be selected from a list of predefined words, and the corresponding question related to the word will be displayed.
2. The word is represented by a series of underscores, each representing a letter of the word. Players need to guess the letters one by one to complete the word.
3. Click on the on-screen keyboard buttons to suggest a letter. If the letter is correct, it will be revealed in the word, and you can continue guessing other letters.
4. If the suggested letter is incorrect, the game will keep track of the wrong guesses. Be careful not to exceed the maximum allowed wrong guesses (currently set to 5), or the game will be over.
5. If you manage to complete the word before reaching the maximum number of wrong guesses, you win the round, and a new word will be presented for the next round.
## How to Run the Game
1. Clone or download the game repository from the provided link.
2. Open the main.html file in a web browser that supports HTML5, CSS3, and JavaScript.
3. The game will load, and you can start playing by interacting with the on-screen keyboard buttons.
4. Enjoy the game and have fun guessing words!
### Screenshots
| Word Guessing Game | Mid-term project | bootstrap5,css,front-end,html5,javascript | 2023-08-01T17:35:27Z | 2023-08-01T14:48:19Z | null | 1 | 0 | 4 | 0 | 0 | 5 | null | null | CSS |
Kaiserabbas/kaiserabbas | main | <p align="center">
<img src="https://github.com/Kaiserabbas/Qaisar-Abbas-Portfolio/raw/main/Images/KAISER-2.png" alt="Your Logo" height="150">
</p>
<p align="center">
<a href="https://www.linkedin.com/in/kaisar-abbas">LinkedIn</a> |
<a href="https://qaisar-abbas-portfolio.vercel.app/">Portfolio</a> |
<a href="https://github.com/Kaiserabbas">GitHub</a>
</p>
<p align="center">
<strong>Phone:</strong> +923140071447 <br>
<strong>Email:</strong> kayser.abbas@gmail.com
</p>
<hr>
<h2>About Me</h2>
<p>
I'm Qaisar, your app developer. I sculpt pixels into front-end landscapes and forge backend logic into steel beams, crafting seamless experiences that feel as natural as a sunrise.
</p>
<p>
With a dynamic background in both software development and agriculture, I bring a unique blend of technical expertise and industry experience. As a dedicated Software Developer, I've developed extensive knowledge in:
</p>
<ul>
<li>Software Development, Object-Oriented Programming, Pair-Programming, Test-driven development</li>
<li>Frontend: Front End Design, HTML5, CSS, JavaScript/React, Redux, API, Frameworks, Bootstrap</li>
<li>Backend: Database-PostgreSQL, Ruby on Rails, Unit Testing, Deployment, Maintenance</li>
<li>Test Driven Development: RSpec, Capybara and Jest</li>
<li>Tools & Methods: Git, GitHub</li>
<li>Landscape Engineering: AutoCAD, Adobe Photoshop, Premier, 3D Realtime Landscape, PunchPro</li>
<li>Communication skills: Bridging Cultural Canyons and building bridges of understanding between diverse teams. No matter the language or culture, I weave clear communication tapestries that foster collaboration and synergy.</li>
<li>Time management: Tasks, time zones, and time itself, I keep everything spinning with a smile, ensuring seamless collaboration even when the clock hands spin at different speeds.</li>
</ul>
<p>
In the past two years, I've embarked on a thrilling journey to become a well-rounded full-stack developer. It hasn't been just about mastering technologies; I've actively honed my communication, collaboration, and problem-solving skills to be a valuable asset to any team. I've built over 15-20 impressive projects, both solo and collaboratively, showcasing my diverse skillset across the tech stacks of HTML/CSS, Ruby/Ruby on Rails, JavaScript, React, and Redux.
</p>
<p>
I consistently exceeded expectations during my time at Microverse, attaining a remarkable 97.6% project completion rate and scoring a stellar 43.9 out of 45 on the final assessment. This achievement reflects my technical prowess, meticulous work ethic, and unwavering commitment to excellence.
</p>
<p>
I'm always eager to learn, experiment, and grow, embracing every opportunity to contribute meaningfully to the tech world. If you'd like to get in contact about potential job opportunities, please reach out! or I love talking with other devs, feel free to connect if you'd like to chat.
</p>
<hr>
<h2>Projects</h2>
<ul>
<li><a href="https://github.com/Kaiserabbas/motorcycle_booking_front_end">Motorcycle Booking / Reservation</a>This Final Capstone Project is a web application that allows users to book an appointment to try a motorcycle. We have followed the design guidelines provided to us, but we have also added some personal touches to the content.
</li>
<li><a href="https://github.com/Kaiserabbas/Budgetify">Budgetify</a>The Ruby on Rails capstone project is about building a mobile web application where you can manage your budget: you have a list of transactions associated with a category, so that you can see how much money you spent and on what.
</li>
<li><a href="https://github.com/Kaiserabbas/food_recipe">Blog App</a>The Recipe app keeps track of all your recipes, ingredients, and inventory. It will allow you to save ingredients, keep track of what you have, create recipes, and generate a shopping list based on what you have and what you are missing from a recipe.
</li>
<li><a href="https://github.com/Kaiserabbas/ruby-group-capstone">Ruby-Capstone-Project3</a> Its a console app that will help you to keep a record of different types of things you own: books, music albums, movies, and games. Everything will be based on the UML class diagram presented below. The data will be stored in JSON files but you will also prepare a database with tables structure analogical to your program's class structure.
</li>
<li><a href="https://github.com/Kaiserabbas/Catalog-of-my-things">Catalog-of-my-things</a>Its a console app that will help you to keep a record of different types of things you own: books, music albums, movies, and games. Everything will be based on the UML class diagram presented below. The data will be stored in JSON files but you will also prepare a database with tables structure analogical to your program's class structure.
</li>
<li><a href="https://github.com/Kaiserabbas/school_library">School Library</a>Its a school library app. In this app, we have implemented the classes to represent students and teachers.
</li>
<li><a href="https://github.com/Kaiserabbas/vet_clinic">Vet Clinic</a>In this project, I have used a relational database to create the initial data structure for a vet clinic. I have created a table to store animals' information, insert some data into it, and query it.
</li>
<li><a href="https://github.com/Kaiserabbas/WeatherApp">Weather App</a>WeatherWise is your all-in-one weather app designed to provide you with accurate, up-to-the-minute weather information, so you can plan your day with confidence. Whether you're planning a weekend getaway, a hiking trip, or just want to know what to wear tomorrow, WeatherWise has got you covered.
</li>
<li><a href="https://github.com/Kaiserabbas/crypto-currencies">Crypto-Currencies API.</a>It is a redux/react web application that works with the real live data from the Crypto-Currencies API. The task is to build a web application for a company that provides Crypto-Currencies and their market price detail services. The application will allow users to view stock prices for Crypto-Currencies and anylize the details.
</li>
<li><a href="https://github.com/Kaiserabbas/Fusion-Bites">Fusion Bites</a>Welcome to Fusion Bites, where culinary artistry meets gastronomic innovation! Our restaurant is a celebration of diverse flavors and cultural influences, creating a harmonious blend of tastes that will tantalize your senses.
</li>
<li><a href="https://github.com/Kaiserabbas/Space-Travelers-Hub">SpaceX Travels API 3</a>It works with the real live data from the SpaceX API. The task is to build a web application for a company that provides commercial and scientific space travel services. The application will allow users to book rockets and join selected space missions.
</li>
<li><a href="https://github.com/Kaiserabbas/continental--cuisine">Continental Classics Cuisine!</a>Welcome to the repository of Continental Classics Cuisine! At our restaurant, we take pride in serving timeless and beloved dishes from the heart of Europe. Explore a curated collection of recipes, cooking techniques, and culinary inspiration that have made our establishment a cherished dining destination.
</li>
<li><a href="https://github.com/Kaiserabbas/bookstore">Book Store</a>Welcome to our bookstore! We are a community of book lovers dedicated to providing a convenient and enjoyable way to discover, read, and discuss books. Our website allows you to: Add books to your personal library Update the percentage of each book that you have read Delete books from your library Add new books to our catalog.
</li>
<li><a href="https://github.com/Kaiserabbas/math-magician">Math Magician</a>It contains React component that will hold the core functionality: a calculator. I have added the logic needed to make the Calculator component to actually work and fetched data from an external API to display "quotes" alongside your calculator.
</li>
<li><a href="https://github.com/Kaiserabbas/Tool-Shed">Tool-Shed</a>We're glad you're here. We've put together a collection of useful tools that we hope you'll find helpful. Here are a few of our most popular tools: Find your IP, random quote, Generate password, weather updates, dictionary and more...
</li>
<li><a href="https://github.com/Kaiserabbas/leaderboard">Leaderboard API service</a>The leaderboard website displays scores submitted by different players. It also allows you to submit your score. All data is preserved thanks to the external Leaderboard API service.
</li>
<li><a href="https://github.com/Kaiserabbas/myday-todo">To-Do List</a>The To-Do List Website is a simple and easy-to-use website that allows you to keep track of your tasks. You can create tasks, set deadlines, and prioritize your tasks. You can also view your tasks in a variety of ways, such as by due date, priority, or category. The To-Do List Website is the perfect way to stay organized and on top of your tasks.
</li>
</ul>
**Education**:
- Full-Stack developer
-- Graduated from Microverse Organization
- Master of Science.
-- University of Agriculture, Faisalabad, Pakistan
**Interests**:
Programming
Web development
Open source
Design Applications
Watching Sports
Looking for a challenging and rewarding opportunity to use my skills and experience to build great products.
## Skills
<div>
## Web Development
[](https://html.spec.whatwg.org/)
[](https://www.w3.org/Style/CSS/)
[](https://developer.mozilla.org/en-US/docs/Web/JavaScript)
[](https://reactjs.org/)
[](https://www.typescriptlang.org/)
[](https://redux.js.org/)
[](https://nodejs.org/)
[](https://expressjs.com/)
[](https://www.ruby-lang.org/en/)
[](https://rubyonrails.org/)
[](https://www.mongodb.com/)
## DevOps & Cloud Services
[](https://www.netlify.com/)
[](https://www.cloudflare.com/)
[](https://vercel.com/)
[](https://render.com/)
[](https://www.heroku.com/)
## Database
[](https://www.postgresql.org/)
[](https://www.mysql.com/)
## Other Skills
[](https://en.wikipedia.org/wiki/Application_programming_interface)
[](https://en.wikipedia.org/wiki/Computer_network)
[](https://en.wikipedia.org/wiki/Front-end_web_development)
[](https://en.wikipedia.org/wiki/Back_end)
</div>
## Tools and Software
In addition to coding, I'm proficient in using various tools and software, including:
- [Canva](https://www.canva.com/)
- [Adobe Photoshop](https://www.adobe.com/products/photoshop.html)
- [Adobe Premiere](https://www.adobe.com/products/premiere.html)
- [Adobe Illustrator](https://www.adobe.com/products/illustrator.html)
- [AutoCAD](https://www.autodesk.com/products/autocad/overview)
- [Microsoft Office Suite](https://www.microsoft.com/en-us/microsoft-365/get-started-with-office-2019)
<div>
[](https://github.com/kaiserabbas/github-contribution-stats/)
</div>
## GitHub Stats
 <br/>
<br/>
| Front-end developer with 3+ years of experience building user-friendly and interactive web applications. Proven ability to work independently and as part of a team to deliver high-quality products. | bootstrap,css,html,javascript,linters-config,webpack | 2023-07-24T09:34:15Z | 2024-02-16T09:46:47Z | null | 1 | 0 | 30 | 0 | 1 | 5 | null | null | null |
Ahmet-Dedeler/ConCussify-CSYA-Hacks | master | # CSYA-Hackathon
## Inspiration
Concussions are known for going undiagnosed, particularly in sports, where there’s pressure to play through injury and more obvious symptoms may not immediately be evident. My sister, for instance, experienced multiple concussions as a competitive cheerleader without realizing, and this resulted in her receiving delayed medical attention and suffering through worsened symptoms. We were motivated to address this problem by developing a convenient and accessible solution for athletes and other individuals prone to concussions, empowering them to independently assess their condition on the spot and seek medical help promptly. By combining a user-friendly and interactive interface with AI features to fill-in for potentially unavailable healthcare professionals, our web app aims to make concussion diagnosis more accessible and efficient than ever before.
## What it does
Concussify determines the likelihood of a concussion based on whether it detects a difference in the pupil size of the right and left eye (a common indication of a concussion). We had also planned for users to be able to take a series of baseline tests that can be repeated after a head injury to determine if there’s been a change in their cognitive speed, memory, or awareness.
## How we built it
The frontend was written in CSS and HTML, and we developed the backend using Cloudflare Workers, which is an edge-based serverless provider that is based upon the WinterCG runtime; through this, we are able to create a highly-scalable and mobile backend able to tackle almost any challenge. We do not have any lock-in as it is based on the Winter CG Runtime which allows us to move to other providers such as Vercel or Deno. We decided to implement Google sign-in to reduce development time while still providing ease-of-use.
The pupil size detection function was built using two pretrained machine learning models. The image is first processed through OpenCV’s Haar Cascade model for eye detection, then the separate eye images are passed through another model which determines pupil diameter.
## Challenges we ran into
We faced several challenges, from differing time zones to part of the team being constrained to work on it for a day and a half. There were communication issues which the differing time zones did not help with, nevertheless, we still tried our hardest to overcome this obstacle and are proud of the accomplishments we achieved.
## Accomplishments that we're proud of
We are proud of the lessons we’ve learned, the challenges we tackled, and our ability to still able to make something in a short timeframe. For some team members, this was their first experience in working in a hackathon, and were therefore quite unused to the format.
## What we learned
Most of us learned more about connecting frontend and backend, as well as working with ML models.
## What's next for Concussify
We hope to extend on our AI model for detecting pupil size, which due to time limits we weren’t able to fully finish and connect to our main app. We also think Concussify could have many more features for evaluating concussion symptoms, such as tests to measure cognitive processing, attention, and memory.
| AI Powered Concussion Detection ⚡ On your browser, in one minute. | ai,data,javascript,web,github,learn | 2023-07-29T23:21:15Z | 2024-02-20T16:20:06Z | null | 4 | 0 | 15 | 0 | 0 | 5 | null | MIT | CSS |
danifromecuador/metrics-app | dev | <a name="readme-top"></a>
<div align="center">
<h3><b>Air Pollution APP</b></h3>
</div>
<!-- TABLE OF CONTENTS -->
# 📗 Table of Contents
- [📖 About the Project](#about-project)
- [🛠 Built With](#built-with)
- [Tech Stack](#tech-stack)
- [Key Features](#key-features)
- [Live Version](#live-version)
- [💻 Getting Started](#getting-started)
- [Prerequisites](#prerequisites)
- [Setup](#setup)
- [Install](#install)
- [Usage](#usage)
- [👥 Authors](#authors)
- [🔭 Future Features](#future-features)
- [🤝 Contributing](#contributing)
- [⭐️ Show your support](#support)
- [🙏 Acknowledgements](#acknowledgements)
- [📝 License](#license)
<!-- PROJECT DESCRIPTION -->
# 📖 Air Pollution APP <a name="about-project"></a>
**Air Pollution APP** uses the Air Pollution API to show how the air health is in different cities around the world.
## 🛠 Built With <a name="built-with"></a>
### Tech Stack <a name="tech-stack"></a>
<details>
<summary>Client</summary>
<ul>
<li><a href="https://reactjs.org/">React.js</a></li>
</ul>
</details>
<!-- Features -->
### Key Features <a name="key-features"></a>
- **The page is built with React and Redux**
- **The page consumes the Air Pollution API**
- **The user can search for a city to view detailed data**
### Live Version <a name="live-version">
[Air Pollution APP](https://64cf19298a3f381144193470--neon-banoffee-55a02e.netlify.app/)
</a>
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- GETTING STARTED -->
## 💻 Getting Started <a name="getting-started"></a>
### Prerequisites
In order to run this project you need:
- Install Git
- Install Node JS
- You can use your favorite CLI and code editor.
### Setup
Clone this repository to your desired folder:
```sh
cd my-folder
git clone git@github.com:danifromecuador/metrics-app.git
```
### Install
Install this project with:
```sh
cd metrics-app
npm install
```
### Usage
To run the project, execute the following command:
```sh
npm run dev
```
Your project should be displayed automatically on your web browser on this port: http://localhost:5173/, if don't open it manually.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- AUTHORS -->
## 👥 Authors <a name="authors"></a>
👤 **Dani Morillo**
- GitHub: [@danifromecuador](https://github.com/danifromecuador)
- Twitter: [@danifromecuador](https://twitter.com/danifromecuador)
- LinkedIn: [danielfromecuador](https://www.linkedin.com/in/danielfromecuador/)
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- FUTURE FEATURES -->
## 🔭 Future Features <a name="future-features"></a>
- **More cities will be added**
- **The user will be able to filter the cities by countries or continents**
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- CONTRIBUTING -->
## 🤝 Contributing <a name="contributing"></a>
Contributions, issues, and feature requests are welcome!
Feel free to check the [issues page](https://github.com/danifromecuador/metrics-app/issues).
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- SUPPORT -->
## ⭐️ Show your support <a name="support"></a>
If you like this project give me a star on my [GitHub Repo](https://github.com/danifromecuador/metrics-app)
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- ACKNOWLEDGEMENTS -->
## 🙏 Acknowledgments <a name="acknowledgements"></a>
If you liked the original design that inspired this project, I recommend you visit [Nelson Sakwa's Behance post](https://www.behance.net/gallery/31579789/Ballhead-App-(Free-PSDs)). and follow him on Behance to support her work.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- LICENSE -->
## 📝 License <a name="license"></a>
This project is [MIT](./LICENSE) licensed.
<p align="right">(<a href="#readme-top">back to top</a>)</p> | Air Pollution APP uses the Air Pollution API to show how the air health is in different cities around the world | gitflow,javascript,netlify,redux,redux-thunk | 2023-07-31T17:06:49Z | 2023-09-08T23:43:00Z | null | 1 | 11 | 98 | 0 | 0 | 5 | null | MIT | JavaScript |
JsIqbal/next-ecommerce | main | null | Admin Portal of E-commerce in Nextjs | clerkauth,env,shadcn-ui,zustand,react-hook-form,zod,mysql,planetscale,prisma,axios | 2023-07-22T10:19:57Z | 2023-08-08T15:46:33Z | null | 2 | 19 | 54 | 0 | 2 | 5 | null | null | TypeScript |
adebola-io/quizwiz | main | <h1 align=center>Quiz Web App</h1>
<p align="center">
<img src="https://img.shields.io/badge/license-MIT-blue" alt="MIT License" />
<a aria-label="last commit" href="https://github.com/adebola-io/quiz-app/commits/main">
<img alt="" src="https://img.shields.io/github/last-commit/adebola-io/quiz-app.svg">
</a>
<a href="https://GitHub.com/adebola-io/quiz-app"><img src="https://img.shields.io/badge/contributors-7-ee8449"/></a>
<a href="http://makeapullrequest.com"><img src="https://img.shields.io/badge/PR(s)-welcome-brightgreen.svg?style=flat-square" alt="Make a pull request."></a>
</p>
This is the repository for Group 3 of the CSC 420 Software Engineering project.
## Design 🖌
The design for this project is hosted on Figma [here](https://www.figma.com/file/AUoDWCLv80ZajCBgePszki/CSC-420---Project?type=design&node-id=0%3A1&mode=design&t=dHfWTuMj0kdoQkOx-1).
## Development 🖥
### Front-end
The front-end is written using React, Typescript and Tailwind. Node and NPM/Yarn must be installed to preview it. To run the frontend locally, cd into the `frontend/` folder and run
```shell
npm install
```
followed by
```shell
npm run dev
```
to start the local dev server.
### Back-end
A simple development back-end is present in the `/backend/mock/` folder. To run it, cd into the folder and run:
```
npm install
```
and then
```shell
npm start
```
to start the Node.js server.
To see the code for the main back-end, visit [here](https://github.com/Matec12/quiz-app-backend).
## Documentation 📜
Relevant documentation files can be viewed in the [`docs`](https://github.com/adebola-io/quiz-app/tree/main/docs) folder.
## Deployment 🚀
All pushes to the `production` branch are automatically deployed on Vercel [here](http://csc420quiz.vercel.app).
| CSC 420 Project - Quiz Game. Built with React, Typescript and Tailwind. | css,javascript,nodejs,react,vite,quiz-game,quizapp | 2023-07-22T12:17:03Z | 2023-08-09T10:19:29Z | null | 10 | 11 | 217 | 0 | 0 | 5 | null | MIT | TypeScript |
BilgeGates/Js-Interview-Questions | master | # JavaScript Interview Questions & Answers
> Click :star:if you like the project and follow [@SudheerJonna](https://twitter.com/SudheerJonna) for more updates. Coding questions available [here](#coding-exercise). PDF and Epub versions available at [actions tab](https://github.com/sudheerj/JavaScript-Interview-Questions/actions).
---
<p align="center">
<a href=https://zerotomastery.io/?utm_source=github&utm_medium=sponsor&utm_campaign=javascript-interview-questions>
<img src=https://process.fs.teachablecdn.com/ADNupMnWyR7kCWRvm76Laz/resize=height:70/https://www.filepicker.io/api/file/AKYtjj5SSGyJuyZrkAB2 alt="ZTM Logo" width="100" height="50">
</a>
<p align="center">
<ol>
<li>Take this <a href=https://links.zerotomastery.io/jsp_sudheer>JavaScript Projects</a> course to go from a JS beginner to confidently building your own projects</li>
<li>Take this <a href=https://links.zerotomastery.io/mci_sudheer2>coding interview bootcamp</a> if you’re serious about getting hired and don’t have a CS degree</li>
<li>Take this <a href=https://links.zerotomastery.io/ajs_sudheer>Advanced JavaScript Course</a> to learn advanced JS concepts and become a top JS developer</li>
</ol>
</p>
</p>
---
### Table of Contents
| No. | Questions |
| --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| 1 | [What are the possible ways to create objects in JavaScript](#what-are-the-possible-ways-to-create-objects-in-javascript) |
| 2 | [What is prototype chain](#what-is-a-prototype-chain) |
| 3 | [What is the difference between Call, Apply and Bind](#what-is-the-difference-between-call-apply-and-bind) |
| 4 | [What is JSON and its common operations](#what-is-json-and-its-common-operations) |
| 5 | [What is the purpose of the array slice method](#what-is-the-purpose-of-the-array-slice-method) |
| 6 | [What is the purpose of the array splice method](#what-is-the-purpose-of-the-array-splice-method) |
| 7 | [What is the difference between slice and splice](#what-is-the-difference-between-slice-and-splice) |
| 8 | [How do you compare Object and Map](#how-do-you-compare-object-and-map) |
| 9 | [What is the difference between == and === operators](#what-is-the-difference-between--and--operators) |
| 10 | [What are lambda or arrow functions](#what-are-lambda-or-arrow-functions) |
| 11 | [What is a first class function](#what-is-a-first-class-function) |
| 12 | [What is a first order function](#what-is-a-first-order-function) |
| 13 | [What is a higher order function](#what-is-a-higher-order-function) |
| 14 | [What is a unary function](#what-is-a-unary-function) |
| 15 | [What is the currying function](#what-is-the-currying-function) |
| 16 | [What is a pure function](#what-is-a-pure-function) |
| 17 | [What is the purpose of the let keyword](#what-is-the-purpose-of-the-let-keyword) |
| 18 | [What is the difference between let and var](#what-is-the-difference-between-let-and-var) |
| 19 | [What is the reason to choose the name let as a keyword](#what-is-the-reason-to-choose-the-name-let-as-a-keyword) |
| 20 | [How do you redeclare variables in switch block without an error](#how-do-you-redeclare-variables-in-switch-block-without-an-error) |
| 21 | [What is the Temporal Dead Zone](#what-is-the-temporal-dead-zone) |
| 22 | [What is IIFE(Immediately Invoked Function Expression)](#what-is-iifeimmediately-invoked-function-expression) |
| 23 | [How do you decode or encode a URL in JavaScript?](#how-do-you-decode-or-encode-a-url-in-javascript) |
| 24 | [What is memoization](#what-is-memoization) |
| 25 | [What is Hoisting](#what-is-hoisting) |
| 26 | [What are classes in ES6](#what-are-classes-in-es6) |
| 27 | [What are closures](#what-are-closures) |
| 28 | [What are modules](#what-are-modules) |
| 29 | [Why do you need modules](#why-do-you-need-modules) |
| 30 | [What is scope in javascript](#what-is-scope-in-javascript) |
| 31 | [What is a service worker](#what-is-a-service-worker) |
| 32 | [How do you manipulate DOM using a service worker](#how-do-you-manipulate-dom-using-a-service-worker) |
| 33 | [How do you reuse information across service worker restarts](#how-do-you-reuse-information-across-service-worker-restarts) |
| 34 | [What is IndexedDB](#what-is-indexeddb) |
| 35 | [What is web storage](#what-is-web-storage) |
| 36 | [What is a post message](#what-is-a-post-message) |
| 37 | [What is a cookie](#what-is-a-cookie) |
| 38 | [Why do you need a Cookie](#why-do-you-need-a-cookie) |
| 39 | [What are the options in a cookie](#what-are-the-options-in-a-cookie) |
| 40 | [How do you delete a cookie](#how-do-you-delete-a-cookie) |
| 41 | [What are the differences between cookie, local storage and session storage](#What-are-the-differences-between-cookie-local-storage-and-session-storage) |
| 42 | [What is the main difference between localStorage and sessionStorage](#what-is-the-main-difference-between-localstorage-and-sessionstorage) |
| 43 | [How do you access web storage](#how-do-you-access-web-storage) |
| 44 | [What are the methods available on session storage](#what-are-the-methods-available-on-session-storage) |
| 45 | [What is a storage event and its event handler](#what-is-a-storage-event-and-its-event-handler) |
| 46 | [Why do you need web storage](#why-do-you-need-web-storage) |
| 47 | [How do you check web storage browser support](#how-do-you-check-web-storage-browser-support) |
| 48 | [How do you check web workers browser support](#how-do-you-check-web-workers-browser-support) |
| 49 | [Give an example of a web worker](#give-an-example-of-a-web-worker) |
| 50 | [What are the restrictions of web workers on DOM](#what-are-the-restrictions-of-web-workers-on-dom) |
| 51 | [What is a promise](#what-is-a-promise) |
| 52 | [Why do you need a promise](#why-do-you-need-a-promise) |
| 53 | [What are the three states of promise](#what-are-the-three-states-of-promise) |
| 54 | [What is a callback function](#what-is-a-callback-function) |
| 55 | [Why do we need callbacks](#why-do-we-need-callbacks) |
| 56 | [What is a callback hell](#what-is-a-callback-hell) |
| 57 | [What are server-sent events](#what-are-server-sent-events) |
| 58 | [How do you receive server-sent event notifications](#how-do-you-receive-server-sent-event-notifications) |
| 59 | [How do you check browser support for server-sent events](#how-do-you-check-browser-support-for-server-sent-events) |
| 60 | [What are the events available for server sent events](#what-are-the-events-available-for-server-sent-events) |
| 61 | [What are the main rules of promise](#what-are-the-main-rules-of-promise) |
| 62 | [What is callback in callback](#what-is-callback-in-callback) |
| 63 | [What is promise chaining](#what-is-promise-chaining) |
| 64 | [What is promise.all](#what-is-promiseall) |
| 65 | [What is the purpose of the race method in promise](#what-is-the-purpose-of-the-race-method-in-promise) |
| 66 | [What is a strict mode in javascript](#what-is-a-strict-mode-in-javascript) |
| 67 | [Why do you need strict mode](#why-do-you-need-strict-mode) |
| 68 | [How do you declare strict mode](#how-do-you-declare-strict-mode) |
| 69 | [What is the purpose of double exclamation](#what-is-the-purpose-of-double-exclamation) |
| 70 | [What is the purpose of the delete operator](#what-is-the-purpose-of-the-delete-operator) |
| 71 | [What is typeof operator](#what-is-typeof-operator) |
| 72 | [What is undefined property](#what-is-undefined-property) |
| 73 | [What is null value](#what-is-null-value) |
| 74 | [What is the difference between null and undefined](#what-is-the-difference-between-null-and-undefined) |
| 75 | [What is eval](#What-is-eval) |
| 76 | [What is the difference between window and document](#what-is-the-difference-between-window-and-document) |
| 77 | [How do you access history in javascript](#how-do-you-access-history-in-javascript) |
| 78 | [How do you detect caps lock key turned on or not](#how-do-you-detect-caps-lock-key-turned-on-or-not) |
| 79 | [What is isNaN](#what-is-isnan) |
| 80 | [What are the differences between undeclared and undefined variables](#what-are-the-differences-between-undeclared-and-undefined-variables) |
| 81 | [What are global variables](#what-are-global-variables) |
| 82 | [What are the problems with global variables](#what-are-the-problems-with-global-variables) |
| 83 | [What is NaN property](#what-is-nan-property) |
| 84 | [What is the purpose of isFinite function](#what-is-the-purpose-of-isfinite-function) |
| 85 | [What is an event flow](#what-is-an-event-flow) |
| 86 | [What is event bubbling](#what-is-event-bubbling) |
| 87 | [What is event capturing](#what-is-event-capturing) |
| 88 | [How do you submit a form using JavaScript](#how-do-you-submit-a-form-using-javascript) |
| 89 | [How do you find operating system details](#how-do-you-find-operating-system-details) |
| 90 | [What is the difference between document load and DOMContentLoaded events](#what-is-the-difference-between-document-load-and-domcontentloaded-events) |
| 91 | [What is the difference between native, host and user objects](#what-is-the-difference-between-native-host-and-user-objects) |
| 92 | [What are the tools or techniques used for debugging JavaScript code](#what-are-the-tools-or-techniques-used-for-debugging-javascript-code) |
| 93 | [What are the pros and cons of promises over callbacks](#what-are-the-pros-and-cons-of-promises-over-callbacks) |
| 94 | [What is the difference between an attribute and a property](#what-is-the-difference-between-an-attribute-and-a-property) |
| 95 | [What is same-origin policy](#what-is-same-origin-policy) |
| 96 | [What is the purpose of void 0](#what-is-the-purpose-of-void-0) |
| 97 | [Is JavaScript a compiled or interpreted language](#is-javascript-a-compiled-or-interpreted-language) |
| 98 | [Is JavaScript a case-sensitive language](#is-javascript-a-case-sensitive-language) |
| 99 | [Is there any relation between Java and JavaScript](#is-there-any-relation-between-java-and-javascript) |
| 100 | [What are events](#what-are-events) |
| 101 | [Who created javascript](#who-created-javascript) |
| 102 | [What is the use of preventDefault method](#what-is-the-use-of-preventdefault-method) |
| 103 | [What is the use of stopPropagation method](#what-is-the-use-of-stoppropagation-method) |
| 104 | [What are the steps involved in return false usage](#what-are-the-steps-involved-in-return-false-usage) |
| 105 | [What is BOM](#what-is-bom) |
| 106 | [What is the use of setTimeout](#what-is-the-use-of-settimeout) |
| 107 | [What is the use of setInterval](#what-is-the-use-of-setinterval) |
| 108 | [Why is JavaScript treated as Single threaded](#why-is-javascript-treated-as-single-threaded) |
| 109 | [What is an event delegation](#what-is-an-event-delegation) |
| 110 | [What is ECMAScript](#what-is-ecmascript) |
| 111 | [What is JSON](#what-is-json) |
| 112 | [What are the syntax rules of JSON](#what-are-the-syntax-rules-of-json) |
| 113 | [What is the purpose JSON stringify](#what-is-the-purpose-json-stringify) |
| 114 | [How do you parse JSON string](#how-do-you-parse-json-string) |
| 115 | [Why do you need JSON](#why-do-you-need-json) |
| 116 | [What are PWAs](#what-are-pwas) |
| 117 | [What is the purpose of clearTimeout method](#what-is-the-purpose-of-cleartimeout-method) |
| 118 | [What is the purpose of clearInterval method](#what-is-the-purpose-of-clearinterval-method) |
| 119 | [How do you redirect new page in javascript](#how-do-you-redirect-new-page-in-javascript) |
| 120 | [How do you check whether a string contains a substring](#how-do-you-check-whether-a-string-contains-a-substring) |
| 121 | [How do you validate an email in javascript](#how-do-you-validate-an-email-in-javascript) |
| 122 | [How do you get the current url with javascript](#how-do-you-get-the-current-url-with-javascript) |
| 123 | [What are the various url properties of location object](#what-are-the-various-url-properties-of-location-object) |
| 124 | [How do get query string values in javascript](#how-do-get-query-string-values-in-javascript) |
| 125 | [How do you check if a key exists in an object](#how-do-you-check-if-a-key-exists-in-an-object) |
| 126 | [How do you loop through or enumerate javascript object](#how-do-you-loop-through-or-enumerate-javascript-object) |
| 127 | [How do you test for an empty object](#how-do-you-test-for-an-empty-object) |
| 128 | [What is an arguments object](#what-is-an-arguments-object) |
| 129 | [How do you make first letter of the string in an uppercase](#how-do-you-make-first-letter-of-the-string-in-an-uppercase) |
| 130 | [What are the pros and cons of for loop](#what-are-the-pros-and-cons-of-for-loop) |
| 131 | [How do you display the current date in javascript](#how-do-you-display-the-current-date-in-javascript) |
| 132 | [How do you compare two date objects](#how-do-you-compare-two-date-objects) |
| 133 | [How do you check if a string starts with another string](#how-do-you-check-if-a-string-starts-with-another-string) |
| 134 | [How do you trim a string in javascript](#how-do-you-trim-a-string-in-javascript) |
| 135 | [How do you add a key value pair in javascript](#how-do-you-add-a-key-value-pair-in-javascript) |
| 136 | [Is the '!--' notation represents a special operator](#is-the----notation-represents-a-special-operator) |
| 137 | [How do you assign default values to variables](#how-do-you-assign-default-values-to-variables) |
| 138 | [How do you define multiline strings](#how-do-you-define-multiline-strings) |
| 139 | [What is an app shell model](#what-is-an-app-shell-model) |
| 140 | [Can we define properties for functions](#can-we-define-properties-for-functions) |
| 141 | [What is the way to find the number of parameters expected by a function](#what-is-the-way-to-find-the-number-of-parameters-expected-by-a-function) |
| 142 | [What is a polyfill](#what-is-a-polyfill) |
| 143 | [What are break and continue statements](#what-are-break-and-continue-statements) |
| 144 | [What are js labels](#what-are-js-labels) |
| 145 | [What are the benefits of keeping declarations at the top](#what-are-the-benefits-of-keeping-declarations-at-the-top) |
| 146 | [What are the benefits of initializing variables](#what-are-the-benefits-of-initializing-variables) |
| 147 | [What are the recommendations to create new object](#what-are-the-recommendations-to-create-new-object) |
| 148 | [How do you define JSON arrays](#how-do-you-define-json-arrays) |
| 149 | [How do you generate random integers](#how-do-you-generate-random-integers) |
| 150 | [Can you write a random integers function to print integers with in a range](#can-you-write-a-random-integers-function-to-print-integers-with-in-a-range) |
| 151 | [What is tree shaking](#what-is-tree-shaking) |
| 152 | [What is the need of tree shaking](#what-is-the-need-of-tree-shaking) |
| 153 | [Is it recommended to use eval](#is-it-recommended-to-use-eval) |
| 154 | [What is a Regular Expression](#what-is-a-regular-expression) |
| 155 | [What are the string methods available in Regular expression](#what-are-the-string-methods-available-in-regular-expression) |
| 156 | [What are modifiers in regular expression](#what-are-modifiers-in-regular-expression) |
| 157 | [What are regular expression patterns](#what-are-regular-expression-patterns) |
| 158 | [What is a RegExp object](#what-is-a-regexp-object) |
| 159 | [How do you search a string for a pattern](#how-do-you-search-a-string-for-a-pattern) |
| 160 | [What is the purpose of exec method](#what-is-the-purpose-of-exec-method) |
| 161 | [How do you change the style of a HTML element](#how-do-you-change-the-style-of-a-html-element) |
| 162 | [What would be the result of 1+2+'3'](#what-would-be-the-result-of-123) |
| 163 | [What is a debugger statement](#what-is-a-debugger-statement) |
| 164 | [What is the purpose of breakpoints in debugging](#what-is-the-purpose-of-breakpoints-in-debugging) |
| 165 | [Can I use reserved words as identifiers](#can-i-use-reserved-words-as-identifiers) |
| 166 | [How do you detect a mobile browser](#how-do-you-detect-a-mobile-browser) |
| 167 | [How do you detect a mobile browser without regexp](#how-do-you-detect-a-mobile-browser-without-regexp) |
| 168 | [How do you get the image width and height using JS](#how-do-you-get-the-image-width-and-height-using-js) |
| 169 | [How do you make synchronous HTTP request](#how-do-you-make-synchronous-http-request) |
| 170 | [How do you make asynchronous HTTP request](#how-do-you-make-asynchronous-http-request) |
| 171 | [How do you convert date to another timezone in javascript](#how-do-you-convert-date-to-another-timezone-in-javascript) |
| 172 | [What are the properties used to get size of window](#what-are-the-properties-used-to-get-size-of-window) |
| 173 | [What is a conditional operator in javascript](#what-is-a-conditional-operator-in-javascript) |
| 174 | [Can you apply chaining on conditional operator](#Can-you-apply-chaining-on-conditional-operator) |
| 175 | [What are the ways to execute javascript after page load](#what-are-the-ways-to-execute-javascript-after-page-load) |
| 176 | [What is the difference between proto and prototype](#what-is-the-difference-between-proto-and-prototype) |
| 177 | [Give an example where do you really need semicolon](#give-an-example-where-do-you-really-need-semicolon) |
| 178 | [What is a freeze method](#what-is-a-freeze-method) |
| 179 | [What is the purpose of freeze method](#what-is-the-purpose-of-freeze-method) |
| 180 | [Why do I need to use freeze method](#why-do-i-need-to-use-freeze-method) |
| 181 | [How do you detect a browser language preference](#how-do-you-detect-a-browser-language-preference) |
| 182 | [How to convert string to title case with javascript](#how-to-convert-string-to-title-case-with-javascript) |
| 183 | [How do you detect javascript disabled in the page](#how-do-you-detect-javascript-disabled-in-the-page) |
| 184 | [What are various operators supported by javascript](#what-are-various-operators-supported-by-javascript) |
| 185 | [What is a rest parameter](#what-is-a-rest-parameter) |
| 186 | [What happens if you do not use rest parameter as a last argument](#what-happens-if-you-do-not-use-rest-parameter-as-a-last-argument) |
| 187 | [What are the bitwise operators available in javascript](#what-are-the-bitwise-operators-available-in-javascript) |
| 188 | [What is a spread operator](#what-is-a-spread-operator) |
| 189 | [How do you determine whether object is frozen or not](#how-do-you-determine-whether-object-is-frozen-or-not) |
| 190 | [How do you determine two values same or not using object](#how-do-you-determine-two-values-same-or-not-using-object) |
| 191 | [What is the purpose of using object is method](#what-is-the-purpose-of-using-object-is-method) |
| 192 | [How do you copy properties from one object to other](#how-do-you-copy-properties-from-one-object-to-other) |
| 193 | [What are the applications of assign method](#what-are-the-applications-of-assign-method) |
| 194 | [What is a proxy object](#what-is-a-proxy-object) |
| 195 | [What is the purpose of seal method](#what-is-the-purpose-of-seal-method) |
| 196 | [What are the applications of seal method](#what-are-the-applications-of-seal-method) |
| 197 | [What are the differences between freeze and seal methods](#what-are-the-differences-between-freeze-and-seal-methods) |
| 198 | [How do you determine if an object is sealed or not](#how-do-you-determine-if-an-object-is-sealed-or-not) |
| 199 | [How do you get enumerable key and value pairs](#how-do-you-get-enumerable-key-and-value-pairs) |
| 200 | [What is the main difference between Object.values and Object.entries method](#what-is-the-main-difference-between-objectvalues-and-objectentries-method) |
| 201 | [How can you get the list of keys of any object](#how-can-you-get-the-list-of-keys-of-any-object) |
| 202 | [How do you create an object with prototype](#how-do-you-create-an-object-with-prototype) |
| 203 | [What is a WeakSet](#what-is-a-weakset) |
| 204 | [What are the differences between WeakSet and Set](#what-are-the-differences-between-weakset-and-set) |
| 205 | [List down the collection of methods available on WeakSet](#list-down-the-collection-of-methods-available-on-weakset) |
| 206 | [What is a WeakMap](#what-is-a-weakmap) |
| 207 | [What are the differences between WeakMap and Map](#what-are-the-differences-between-weakmap-and-map) |
| 208 | [List down the collection of methods available on WeakMap](#list-down-the-collection-of-methods-available-on-weakmap) |
| 209 | [What is the purpose of uneval](#what-is-the-purpose-of-uneval) |
| 210 | [How do you encode an URL](#how-do-you-encode-an-url) |
| 211 | [How do you decode an URL](#how-do-you-decode-an-url) |
| 212 | [How do you print the contents of web page](#how-do-you-print-the-contents-of-web-page) |
| 213 | [What is the difference between uneval and eval](#what-is-the-difference-between-uneval-and-eval) |
| 214 | [What is an anonymous function](#what-is-an-anonymous-function) |
| 215 | [What is the precedence order between local and global variables](#what-is-the-precedence-order-between-local-and-global-variables) |
| 216 | [What are javascript accessors](#what-are-javascript-accessors) |
| 217 | [How do you define property on Object constructor](#how-do-you-define-property-on-object-constructor) |
| 218 | [What is the difference between get and defineProperty](#what-is-the-difference-between-get-and-defineproperty) |
| 219 | [What are the advantages of Getters and Setters](#what-are-the-advantages-of-getters-and-setters) |
| 220 | [Can I add getters and setters using defineProperty method](#can-i-add-getters-and-setters-using-defineproperty-method) |
| 221 | [What is the purpose of switch-case](#what-is-the-purpose-of-switch-case) |
| 222 | [What are the conventions to be followed for the usage of switch case](#what-are-the-conventions-to-be-followed-for-the-usage-of-switch-case) |
| 223 | [What are primitive data types](#what-are-primitive-data-types) |
| 224 | [What are the different ways to access object properties](#what-are-the-different-ways-to-access-object-properties) |
| 225 | [What are the function parameter rules](#what-are-the-function-parameter-rules) |
| 226 | [What is an error object](#what-is-an-error-object) |
| 227 | [When you get a syntax error](#when-you-get-a-syntax-error) |
| 228 | [What are the different error names from error object](#what-are-the-different-error-names-from-error-object) |
| 229 | [What are the various statements in error handling](#what-are-the-various-statements-in-error-handling) |
| 230 | [What are the two types of loops in javascript](#what-are-the-two-types-of-loops-in-javascript) |
| 231 | [What is nodejs](#what-is-nodejs) |
| 232 | [What is an Intl object](#what-is-an-intl-object) |
| 233 | [How do you perform language specific date and time formatting](#how-do-you-perform-language-specific-date-and-time-formatting) |
| 234 | [What is an Iterator](#what-is-an-iterator) |
| 235 | [How does synchronous iteration works](#how-does-synchronous-iteration-works) |
| 236 | [What is an event loop](#what-is-an-event-loop) |
| 237 | [What is call stack](#what-is-call-stack) |
| 238 | [What is an event queue](#what-is-an-event-queue) |
| 239 | [What is a decorator](#what-is-a-decorator) |
| 240 | [What are the properties of Intl object](#what-are-the-properties-of-intl-object) |
| 241 | [What is an Unary operator](#what-is-an-unary-operator) |
| 242 | [How do you sort elements in an array](#how-do-you-sort-elements-in-an-array) |
| 243 | [What is the purpose of compareFunction while sorting arrays](#what-is-the-purpose-of-comparefunction-while-sorting-arrays) |
| 244 | [How do you reversing an array](#how-do-you-reversing-an-array) |
| 245 | [How do you find min and max value in an array](#how-do-you-find-min-and-max-value-in-an-array) |
| 246 | [How do you find min and max values without Math functions](#how-do-you-find-min-and-max-values-without-math-functions) |
| 247 | [What is an empty statement and purpose of it](#what-is-an-empty-statement-and-purpose-of-it) |
| 248 | [How do you get metadata of a module](#how-do-you-get-metadata-of-a-module) |
| 249 | [What is a comma operator](#what-is-a-comma-operator) |
| 250 | [What is the advantage of a comma operator](#what-is-the-advantage-of-a-comma-operator) |
| 251 | [What is typescript](#what-is-typescript) |
| 252 | [What are the differences between javascript and typescript](#what-are-the-differences-between-javascript-and-typescript) |
| 253 | [What are the advantages of typescript over javascript](#what-are-the-advantages-of-typescript-over-javascript) |
| 254 | [What is an object initializer](#what-is-an-object-initializer) |
| 255 | [What is a constructor method](#what-is-a-constructor-method) |
| 256 | [What happens if you write constructor more than once in a class](#what-happens-if-you-write-constructor-more-than-once-in-a-class) |
| 257 | [How do you call the constructor of a parent class](#how-do-you-call-the-constructor-of-a-parent-class) |
| 258 | [How do you get the prototype of an object](#how-do-you-get-the-prototype-of-an-object) |
| 259 | [What happens If I pass string type for getPrototype method](#what-happens-if-i-pass-string-type-for-getprototype-method) |
| 260 | [How do you set prototype of one object to another](#how-do-you-set-prototype-of-one-object-to-another) |
| 261 | [How do you check whether an object can be extendable or not](#how-do-you-check-whether-an-object-can-be-extendable-or-not) |
| 262 | [How do you prevent an object to extend](#how-do-you-prevent-an-object-to-extend) |
| 263 | [What are the different ways to make an object non-extensible](#what-are-the-different-ways-to-make-an-object-non-extensible) |
| 264 | [How do you define multiple properties on an object](#how-do-you-define-multiple-properties-on-an-object) |
| 265 | [What is MEAN in javascript](#what-is-mean-in-javascript) |
| 266 | [What Is Obfuscation in javascript](#what-is-obfuscation-in-javascript) |
| 267 | [Why do you need Obfuscation](#why-do-you-need-obfuscation) |
| 268 | [What is Minification](#what-is-minification) |
| 269 | [What are the advantages of minification](#what-are-the-advantages-of-minification) |
| 270 | [What are the differences between Obfuscation and Encryption](#what-are-the-differences-between-obfuscation-and-encryption) |
| 271 | [What are the common tools used for minification](#what-are-the-common-tools-used-for-minification) |
| 272 | [How do you perform form validation using javascript](#how-do-you-perform-form-validation-using-javascript) |
| 273 | [How do you perform form validation without javascript](#how-do-you-perform-form-validation-without-javascript) |
| 274 | [What are the DOM methods available for constraint validation](#what-are-the-dom-methods-available-for-constraint-validation) |
| 275 | [What are the available constraint validation DOM properties](#what-are-the-available-constraint-validation-dom-properties) |
| 276 | [What are the list of validity properties](#what-are-the-list-of-validity-properties) |
| 277 | [Give an example usage of rangeOverflow property](#give-an-example-usage-of-rangeoverflow-property) |
| 278 | [Is enums feature available in javascript](#is-enums-feature-available-in-javascript) |
| 279 | [What is an enum](#What-is-an-enum) |
| 280 | [How do you list all properties of an object](#how-do-you-list-all-properties-of-an-object) |
| 281 | [How do you get property descriptors of an object](#how-do-you-get-property-descriptors-of-an-object) |
| 282 | [What are the attributes provided by a property descriptor](#what-are-the-attributes-provided-by-a-property-descriptor) |
| 283 | [How do you extend classes](#how-do-you-extend-classes) |
| 284 | [How do I modify the url without reloading the page](#how-do-i-modify-the-url-without-reloading-the-page) |
| 285 | [How do you check whether an array includes a particular value or not](#how-do-you-check-whether-an-array-includes-a-particular-value-or-not) |
| 286 | [How do you compare scalar arrays](#how-do-you-compare-scalar-arrays) |
| 287 | [How to get the value from get parameters](#how-to-get-the-value-from-get-parameters) |
| 288 | [How do you print numbers with commas as thousand separators](#how-do-you-print-numbers-with-commas-as-thousand-separators) |
| 289 | [What is the difference between java and javascript](#what-is-the-difference-between-java-and-javascript) |
| 290 | [Does javascript supports namespace](#does-javascript-supports-namespace) |
| 291 | [How do you declare namespace](#how-do-you-declare-namespace) |
| 292 | [How do you invoke javascript code in an iframe from parent page](#how-do-you-invoke-javascript-code-in-an-iframe-from-parent-page) |
| 293 | [How do get the timezone offset from date](#how-do-get-the-timezone-offset-from-date) |
| 294 | [How do you load CSS and JS files dynamically](#how-do-you-load-css-and-js-files-dynamically) |
| 295 | [What are the different methods to find HTML elements in DOM](#what-are-the-different-methods-to-find-html-elements-in-dom) |
| 296 | [What is jQuery](#what-is-jquery) |
| 297 | [What is V8 JavaScript engine](#what-is-v8-javascript-engine) |
| 298 | [Why do we call javascript as dynamic language](#why-do-we-call-javascript-as-dynamic-language) |
| 299 | [What is a void operator](#what-is-a-void-operator) |
| 300 | [How to set the cursor to wait](#how-to-set-the-cursor-to-wait) |
| 301 | [How do you create an infinite loop](#how-do-you-create-an-infinite-loop) |
| 302 | [Why do you need to avoid with statement](#why-do-you-need-to-avoid-with-statement) |
| 303 | [What is the output of below for loops](#what-is-the-output-of-below-for-loops) |
| 304 | [List down some of the features of ES6](#list-down-some-of-the-features-of-es6) |
| 305 | [What is ES6](#what-is-es6) |
| 306 | [Can I redeclare let and const variables](#can-I-redeclare-let-and-const-variables) |
| 307 | [Is const variable makes the value immutable](#is-const-variable-makes-the-value-immutable) |
| 308 | [What are default parameters](#what-are-default-parameters) |
| 309 | [What are template literals](#what-are-template-literals) |
| 310 | [How do you write multi-line strings in template literals](#how-do-you-write-multi-line-strings-in-template-literals) |
| 311 | [What are nesting templates](#what-are-nesting-templates) |
| 312 | [What are tagged templates](#what-are-tagged-templates) |
| 313 | [What are raw strings](#what-are-raw-strings) |
| 314 | [What is destructuring assignment](#what-is-destructuring-assignment) |
| 315 | [What are default values in destructuring assignment](#what-are-default-values-in-destructuring-assignment) |
| 316 | [How do you swap variables in destructuring assignment](#how-do-you-swap-variables-in-destructuring-assignment) |
| 317 | [What are enhanced object literals](#what-are-enhanced-object-literals) |
| 318 | [What are dynamic imports](#what-are-dynamic-imports) |
| 319 | [What are the use cases for dynamic imports](#what-are-the-use-cases-for-dynamic-imports) |
| 320 | [What are typed arrays](#what-are-typed-arrays) |
| 321 | [What are the advantages of module loaders](#what-are-the-advantages-of-module-loaders) |
| 322 | [What is collation](#what-is-collation) |
| 323 | [What is for...of statement](#what-is-forof-statement) |
| 324 | [What is the output of below spread operator array](#what-is-the-output-of-below-spread-operator-array) |
| 325 | [Is PostMessage secure](#is-postmessage-secure) |
| 326 | [What are the problems with postmessage target origin as wildcard](#what-are-the-problems-with-postmessage-target-origin-as-wildcard) |
| 327 | [How do you avoid receiving postMessages from attackers](#how-do-you-avoid-receiving-postmessages-from-attackers) |
| 328 | [Can I avoid using postMessages completely](#can-i-avoid-using-postmessages-completely) |
| 329 | [Is postMessages synchronous](#is-postmessages-synchronous) |
| 330 | [What paradigm is Javascript](#what-paradigm-is-javascript) |
| 331 | [What is the difference between internal and external javascript](#what-is-the-difference-between-internal-and-external-javascript) |
| 332 | [Is JavaScript faster than server side script](#is-javascript-faster-than-server-side-script) |
| 333 | [How do you get the status of a checkbox](#how-do-you-get-the-status-of-a-checkbox) |
| 334 | [What is the purpose of double tilde operator](#what-is-the-purpose-of-double-tilde-operator) |
| 335 | [How do you convert character to ASCII code](#how-do-you-convert-character-to-ascii-code) |
| 336 | [What is ArrayBuffer](#what-is-arraybuffer) |
| 337 | [What is the output of below string expression](#what-is-the-output-of-below-string-expression) |
| 338 | [What is the purpose of Error object](#what-is-the-purpose-of-error-object) |
| 339 | [What is the purpose of EvalError object](#what-is-the-purpose-of-evalerror-object) |
| 340 | [What are the list of cases error thrown from non-strict mode to strict mode](#what-are-the-list-of-cases-error-thrown-from-non-strict-mode-to-strict-mode) |
| 341 | [Do all objects have prototypes](#do-all-objects-have-prototypes) |
| 342 | [What is the difference between a parameter and an argument](#what-is-the-difference-between-a-parameter-and-an-argument) |
| 343 | [What is the purpose of some method in arrays](#what-is-the-purpose-of-some-method-in-arrays) |
| 344 | [How do you combine two or more arrays](#how-do-you-combine-two-or-more-arrays) |
| 345 | [What is the difference between Shallow and Deep copy](#what-is-the-difference-between-shallow-and-deep-copy) |
| 346 | [How do you create specific number of copies of a string](#how-do-you-create-specific-number-of-copies-of-a-string) |
| 347 | [How do you return all matching strings against a regular expression](#how-do-you-return-all-matching-strings-against-a-regular-expression) |
| 348 | [How do you trim a string at the beginning or ending](#how-do-you-trim-a-string-at-the-beginning-or-ending) |
| 349 | [What is the output of below console statement with unary operator](#what-is-the-output-of-below-console-statement-with-unary-operator) |
| 350 | [Does javascript uses mixins](#does-javascript-uses-mixins) |
| 351 | [What is a thunk function](#what-is-a-thunk-function) |
| 352 | [What are asynchronous thunks](#what-are-asynchronous-thunks) |
| 353 | [What is the output of below function calls](#what-is-the-output-of-below-function-calls) |
| 354 | [How to remove all line breaks from a string](#how-to-remove-all-line-breaks-from-a-string) |
| 355 | [What is the difference between reflow and repaint](#what-is-the-difference-between-reflow-and-repaint) |
| 356 | [What happens with negating an array](#what-happens-with-negating-an-array) |
| 357 | [What happens if we add two arrays](#what-happens-if-we-add-two-arrays) |
| 358 | [What is the output of prepend additive operator on falsy values](#what-is-the-output-of-prepend-additive-operator-on-falsy-values) |
| 359 | [How do you create self string using special characters](#how-do-you-create-self-string-using-special-characters) |
| 360 | [How do you remove falsy values from an array](#how-do-you-remove-falsy-values-from-an-array) |
| 361 | [How do you get unique values of an array](#how-do-you-get-unique-values-of-an-array) |
| 362 | [What is destructuring aliases](#what-is-destructuring-aliases) |
| 363 | [How do you map the array values without using map method](#how-do-you-map-the-array-values-without-using-map-method) |
| 364 | [How do you empty an array](#how-do-you-empty-an-array) |
| 365 | [How do you rounding numbers to certain decimals](#how-do-you-rounding-numbers-to-certain-decimals) |
| 366 | [What is the easiest way to convert an array to an object](#what-is-the-easiest-way-to-convert-an-array-to-an-object) |
| 367 | [How do you create an array with some data](#how-do-you-create-an-array-with-some-data) |
| 368 | [What are the placeholders from console object](#what-are-the-placeholders-from-console-object) |
| 369 | [Is it possible to add CSS to console messages](#is-it-possible-to-add-css-to-console-messages) |
| 370 | [What is the purpose of dir method of console object](#what-is-the-purpose-of-dir-method-of-console-object) |
| 371 | [Is it possible to debug HTML elements in console](#is-it-possible-to-debug-html-elements-in-console) |
| 372 | [How do you display data in a tabular format using console object](#how-do-you-display-data-in-a-tabular-format-using-console-object) |
| 373 | [How do you verify that an argument is a Number or not](#how-do-you-verify-that-an-argument-is-a-number-or-not) |
| 374 | [How do you create copy to clipboard button](#how-do-you-create-copy-to-clipboard-button) |
| 375 | [What is the shortcut to get timestamp](#what-is-the-shortcut-to-get-timestamp) |
| 376 | [How do you flattening multi dimensional arrays](#how-do-you-flattening-multi-dimensional-arrays) |
| 377 | [What is the easiest multi condition checking](#what-is-the-easiest-multi-condition-checking) |
| 378 | [How do you capture browser back button](#how-do-you-capture-browser-back-button) |
| 379 | [How do you disable right click in the web page](#how-do-you-disable-right-click-in-the-web-page) |
| 380 | [What are wrapper objects](#what-are-wrapper-objects) |
| 381 | [What is AJAX](#what-is-ajax) |
| 382 | [What are the different ways to deal with Asynchronous Code](#what-are-the-different-ways-to-deal-with-asynchronous-code) |
| 383 | [How to cancel a fetch request](#how-to-cancel-a-fetch-request) |
| 384 | [What is web speech API](#what-is-web-speech-api) |
| 385 | [What is minimum timeout throttling](#what-is-minimum-timeout-throttling) |
| 386 | [How do you implement zero timeout in modern browsers](#how-do-you-implement-zero-timeout-in-modern-browsers) |
| 387 | [What are tasks in event loop](#what-are-tasks-in-event-loop) |
| 388 | [What is microtask](#what-is-microtask) |
| 389 | [What are different event loops](#what-are-different-event-loops) |
| 390 | [What is the purpose of queueMicrotask](#what-is-the-purpose-of-queuemicrotask) |
| 391 | [How do you use javascript libraries in typescript file](#how-do-you-use-javascript-libraries-in-typescript-file) |
| 392 | [What are the differences between promises and observables](#what-are-the-differences-between-promises-and-observables) |
| 393 | [What is heap](#what-is-heap) |
| 394 | [What is an event table](#what-is-an-event-table) |
| 395 | [What is a microTask queue](#what-is-a-microtask-queue) |
| 396 | [What is the difference between shim and polyfill](#what-is-the-difference-between-shim-and-polyfill) |
| 397 | [How do you detect primitive or non primitive value type](#how-do-you-detect-primitive-or-non-primitive-value-type) |
| 398 | [What is babel](#what-is-babel) |
| 399 | [Is Node.js completely single threaded](#is-nodejs-completely-single-threaded) |
| 400 | [What are the common use cases of observables](#what-are-the-common-use-cases-of-observables) |
| 401 | [What is RxJS](#what-is-rxjs) |
| 402 | [What is the difference between Function constructor and function declaration](#what-is-the-difference-between-function-constructor-and-function-declaration) |
| 403 | [What is a Short circuit condition](#what-is-a-short-circuit-condition) |
| 404 | [What is the easiest way to resize an array](#what-is-the-easiest-way-to-resize-an-array) |
| 405 | [What is an observable](#what-is-an-observable) |
| 406 | [What is the difference between function and class declarations](#what-is-the-difference-between-function-and-class-declarations) |
| 407 | [What is an async function](#what-is-an-async-function) |
| 408 | [How do you prevent promises swallowing errors](#how-do-you-prevent-promises-swallowing-errors) |
| 409 | [What is deno](#what-is-deno) |
| 410 | [How do you make an object iterable in javascript](#how-do-you-make-an-object-iterable-in-javascript) |
| 411 | [What is a Proper Tail Call](#what-is-a-proper-tail-call) |
| 412 | [How do you check an object is a promise or not](#how-do-you-check-an-object-is-a-promise-or-not) |
| 413 | [How to detect if a function is called as constructor](#how-to-detect-if-a-function-is-called-as-constructor) |
| 414 | [What are the differences between arguments object and rest parameter](#what-are-the-differences-between-arguments-object-and-rest-parameter) |
| 415 | [What are the differences between spread operator and rest parameter](#what-are-the-differences-between-spread-operator-and-rest-parameter) |
| 416 | [What are the different kinds of generators](#what-are-the-different-kinds-of-generators) |
| 417 | [What are the built-in iterables](#what-are-the-built-in-iterables) |
| 418 | [What are the differences between for...of and for...in statements](#what-are-the-differences-between-forof-and-forin-statements) |
| 419 | [How do you define instance and non-instance properties](#how-do-you-define-instance-and-non-instance-properties) |
| 420 | [What is the difference between isNaN and Number.isNaN?](#what-is-the-difference-between-isnan-and-numberisnan) |
| 421 | [How to invoke an IIFE without any extra brackets?](#how-to-invoke-an-iife-without-any-extra-brackets) |
| 422 | [Is that possible to use expressions in switch cases?](#is-that-possible-to-use-expressions-in-switch-cases) |
| 423 | [What is the easiest way to ignore promise errors?](#what-is-the-easiest-way-to-ignore-promise-errors) |
| 424 | [How do style the console output using CSS?](#how-do-style-the-console-output-using-css) |
| 425 | [What is nullish coalescing operator (??)?](#what-is-nullish-coalescing-operator) |
| 426 | [How do you group and nest console output?](#how-do-you-group-and-nest-console-output) |
| 427 | [What is the difference between dense and sparse arrays?](#what-is-the-difference-between-dense-and-sparse-arrays) |
| 428 | [What are the different ways to create sparse arrays?](#what-are-the-different-ways-to-create-sparse-arrays) |
| 429 | [What is the difference between setTimeout, setImmediate and process.nextTick?](#what-is-the-difference-between-settimeout-setimmediate-and-processnexttick) |
| 430 | [How do you reverse an array without modifying original array?](#how-do-you-reverse-an-array-without-modifying-original-array) |
| 431 | [How do you create custom HTML element?](#how-do-you-create-custom-html-element) |
| 432 | [What is global execution context?](#what-is-global-execution-context) |
| 433 | [What is function execution context?](#what-is-function-execution-context) |
| 434 | [What is debouncing?](#what-is-debouncing) |
| 435 | [What is throttling?](#what-is-throttling) |
| 436 | [What is optional chaining?](#what-is-optional-chaining) |
| 437 | [What is an environment record?](#what-is-an-environment-record) |
| 438 | [How to verify if a variable is an array?](#how-to-verify-if-a-variable-is-an-array) |
| 439 | [What is pass by value and pass by reference?](#what-is-pass-by-value-and-pass-by-reference) |
| 440 | [What are the differences between primitives and non-primitives?](#what-are-the-differences-between-primitives-and-non-primitives) |
| 441 | [What are hidden classes?](#what-are-hidden-classes) |
| 442 | [What is inline caching?](#what-is-inline-caching) |
| 443 | [How do you create your own bind method using either call or apply method?](#how-do-you-create-your-own-bind-method-using-either-call-or-apply-method) |
| 444 | [What are the differences between pure and impure functions?](#what-are-the-differences-between-pure-and-impure-functions?)
| 445 | [What is referential transparency?](#what-is-referential-transparency) |
| 446 | [What are the possible side-effects in javascript?](#what-are-the-possible-side-effects-in-javascript) |
| 447 | [What are compose and pipe functions?](#what-are-compose-and-pipe-functions) |
| 448 | [What is module pattern?](#what-is-module-pattern) |
| 449 | [What is Functon Composition?](#what-is-function-composition) |
| 450 | [How to use await outside of async function prior to ES2022?](#how-to-use-await-outside-of-async-function-prior-to-es2022) |
1. ### What are the possible ways to create objects in JavaScript
There are many ways to create objects in javascript as below
1. **Object constructor:**
The simplest way to create an empty object is using the Object constructor. Currently this approach is not recommended.
```javascript
var object = new Object();
```
2. **Object's create method:**
The create method of Object creates a new object by passing the prototype object as a parameter
```javascript
var object = Object.create(null);
```
3. **Object literal syntax:**
The object literal syntax (or object initializer), is a comma-separated set of name-value pairs wrapped in curly braces.
```javascript
var object = {
name: "Sudheer",
age: 34
};
Object literal property values can be of any data type, including array, function, and nested object.
```
**Note:** This is an easiest way to create an object
4. **Function constructor:**
Create any function and apply the new operator to create object instances,
```javascript
function Person(name) {
this.name = name;
this.age = 21;
}
var object = new Person("Sudheer");
```
5. **Function constructor with prototype:**
This is similar to function constructor but it uses prototype for their properties and methods,
```javascript
function Person() {}
Person.prototype.name = "Sudheer";
var object = new Person();
```
This is equivalent to an instance created with an object create method with a function prototype and then call that function with an instance and parameters as arguments.
```javascript
function func() {};
new func(x, y, z);
```
**(OR)**
```javascript
// Create a new instance using function prototype.
var newInstance = Object.create(func.prototype)
// Call the function
var result = func.call(newInstance, x, y, z),
// If the result is a non-null object then use it otherwise just use the new instance.
console.log(result && typeof result === 'object' ? result : newInstance);
```
6. **ES6 Class syntax:**
ES6 introduces class feature to create the objects
```javascript
class Person {
constructor(name) {
this.name = name;
}
}
var object = new Person("Sudheer");
```
7. **Singleton pattern:**
A Singleton is an object which can only be instantiated one time. Repeated calls to its constructor return the same instance and this way one can ensure that they don't accidentally create multiple instances.
```javascript
var object = new (function () {
this.name = "Sudheer";
})();
```
**[⬆ Back to Top](#table-of-contents)**
2. ### What is a prototype chain
**Prototype chaining** is used to build new types of objects based on existing ones. It is similar to inheritance in a class based language.
The prototype on object instance is available through **Object.getPrototypeOf(object)** or **\_\_proto__** property whereas prototype on constructors function is available through **Object.prototype**.
**[⬆ Back to Top](#table-of-contents)**
3. ### What is the difference between Call, Apply and Bind
The difference between Call, Apply and Bind can be explained with below examples,
**Call:** The call() method invokes a function with a given `this` value and arguments provided one by one
```javascript
var employee1 = { firstName: "John", lastName: "Rodson" };
var employee2 = { firstName: "Jimmy", lastName: "Baily" };
function invite(greeting1, greeting2) {
console.log(
greeting1 + " " + this.firstName + " " + this.lastName + ", " + greeting2
);
}
invite.call(employee1, "Hello", "How are you?"); // Hello John Rodson, How are you?
invite.call(employee2, "Hello", "How are you?"); // Hello Jimmy Baily, How are you?
```
**Apply:** Invokes the function with a given `this` value and allows you to pass in arguments as an array
```javascript
var employee1 = { firstName: "John", lastName: "Rodson" };
var employee2 = { firstName: "Jimmy", lastName: "Baily" };
function invite(greeting1, greeting2) {
console.log(
greeting1 + " " + this.firstName + " " + this.lastName + ", " + greeting2
);
}
invite.apply(employee1, ["Hello", "How are you?"]); // Hello John Rodson, How are you?
invite.apply(employee2, ["Hello", "How are you?"]); // Hello Jimmy Baily, How are you?
```
**bind:** returns a new function, allowing you to pass any number of arguments
```javascript
var employee1 = { firstName: "John", lastName: "Rodson" };
var employee2 = { firstName: "Jimmy", lastName: "Baily" };
function invite(greeting1, greeting2) {
console.log(
greeting1 + " " + this.firstName + " " + this.lastName + ", " + greeting2
);
}
var inviteEmployee1 = invite.bind(employee1);
var inviteEmployee2 = invite.bind(employee2);
inviteEmployee1("Hello", "How are you?"); // Hello John Rodson, How are you?
inviteEmployee2("Hello", "How are you?"); // Hello Jimmy Baily, How are you?
```
Call and apply are pretty interchangeable. Both execute the current function immediately. You need to decide whether it’s easier to send in an array or a comma separated list of arguments. You can remember by treating Call is for **comma** (separated list) and Apply is for **Array**.
Whereas Bind creates a new function that will have `this` set to the first parameter passed to bind().
**[⬆ Back to Top](#table-of-contents)**
4. ### What is JSON and its common operations
**JSON** is a text-based data format following JavaScript object syntax, which was popularized by `Douglas Crockford`. It is useful when you want to transmit data across a network and it is basically just a text file with an extension of .json, and a MIME type of application/json
**Parsing:** Converting a string to a native object
```javascript
JSON.parse(text);
```
**Stringification:** converting a native object to a string so it can be transmitted across the network
```javascript
JSON.stringify(object);
```
**[⬆ Back to Top](#table-of-contents)**
5. ### What is the purpose of the array slice method
The **slice()** method returns the selected elements in an array as a new array object. It selects the elements starting at the given start argument, and ends at the given optional end argument without including the last element. If you omit the second argument then it selects till the end.
Some of the examples of this method are,
```javascript
let arrayIntegers = [1, 2, 3, 4, 5];
let arrayIntegers1 = arrayIntegers.slice(0, 2); // returns [1,2]
let arrayIntegers2 = arrayIntegers.slice(2, 3); // returns [3]
let arrayIntegers3 = arrayIntegers.slice(4); //returns [5]
```
**Note:** Slice method won't mutate the original array but it returns the subset as a new array.
**[⬆ Back to Top](#table-of-contents)**
6. ### What is the purpose of the array splice method
The **splice()** method is used either adds/removes items to/from an array, and then returns the removed item. The first argument specifies the array position for insertion or deletion whereas the optional second argument indicates the number of elements to be deleted. Each additional argument is added to the array.
Some of the examples of this method are,
```javascript
let arrayIntegersOriginal1 = [1, 2, 3, 4, 5];
let arrayIntegersOriginal2 = [1, 2, 3, 4, 5];
let arrayIntegersOriginal3 = [1, 2, 3, 4, 5];
let arrayIntegers1 = arrayIntegersOriginal1.splice(0, 2); // returns [1, 2]; original array: [3, 4, 5]
let arrayIntegers2 = arrayIntegersOriginal2.splice(3); // returns [4, 5]; original array: [1, 2, 3]
let arrayIntegers3 = arrayIntegersOriginal3.splice(3, 1, "a", "b", "c"); //returns [4]; original array: [1, 2, 3, "a", "b", "c", 5]
```
**Note:** Splice method modifies the original array and returns the deleted array.
**[⬆ Back to Top](#table-of-contents)**
7. ### What is the difference between slice and splice
Some of the major difference in a tabular form
| Slice | Splice |
| -------------------------------------------- | ----------------------------------------------- |
| Doesn't modify the original array(immutable) | Modifies the original array(mutable) |
| Returns the subset of original array | Returns the deleted elements as array |
| Used to pick the elements from array | Used to insert or delete elements to/from array |
**[⬆ Back to Top](#table-of-contents)**
8. ### How do you compare Object and Map
**Objects** are similar to **Maps** in that both let you set keys to values, retrieve those values, delete keys, and detect whether something is stored at a key. Due to this reason, Objects have been used as Maps historically. But there are important differences that make using a Map preferable in certain cases.
1. The keys of an Object are Strings and Symbols, whereas they can be any value for a Map, including functions, objects, and any primitive.
2. The keys in Map are ordered while keys added to Object are not. Thus, when iterating over it, a Map object returns keys in order of insertion.
3. You can get the size of a Map easily with the size property, while the number of properties in an Object must be determined manually.
4. A Map is an iterable and can thus be directly iterated, whereas iterating over an Object requires obtaining its keys in some fashion and iterating over them.
5. An Object has a prototype, so there are default keys in the map that could collide with your keys if you're not careful. As of ES5 this can be bypassed by using map = Object.create(null), but this is seldom done.
6. A Map may perform better in scenarios involving frequent addition and removal of key pairs.
**[⬆ Back to Top](#table-of-contents)**
9. ### What is the difference between == and === operators
JavaScript provides both strict(===, !==) and type-converting(==, !=) equality comparison. The strict operators take type of variable in consideration, while non-strict operators make type correction/conversion based upon values of variables. The strict operators follow the below conditions for different types,
1. Two strings are strictly equal when they have the same sequence of characters, same length, and same characters in corresponding positions.
2. Two numbers are strictly equal when they are numerically equal. i.e, Having the same number value.
There are two special cases in this,
1. NaN is not equal to anything, including NaN.
2. Positive and negative zeros are equal to one another.
3. Two Boolean operands are strictly equal if both are true or both are false.
4. Two objects are strictly equal if they refer to the same Object.
5. Null and Undefined types are not equal with ===, but equal with ==. i.e,
null===undefined --> false but null==undefined --> true
Some of the example which covers the above cases,
```javascript
0 == false // true
0 === false // false
1 == "1" // true
1 === "1" // false
null == undefined // true
null === undefined // false
'0' == false // true
'0' === false // false
[]==[] or []===[] //false, refer different objects in memory
{}=={} or {}==={} //false, refer different objects in memory
```
**[⬆ Back to Top](#table-of-contents)**
10. ### What are lambda or arrow functions
An arrow function is a shorter syntax for a function expression and does not have its own **this, arguments, super, or new.target**. These functions are best suited for non-method functions, and they cannot be used as constructors.
**[⬆ Back to Top](#table-of-contents)**
11. ### What is a first class function
In Javascript, functions are first class objects. First-class functions means when functions in that language are treated like any other variable.
For example, in such a language, a function can be passed as an argument to other functions, can be returned by another function and can be assigned as a value to a variable. For example, in the below example, handler functions assigned to a listener
```javascript
const handler = () => console.log("This is a click handler function");
document.addEventListener("click", handler);
```
**[⬆ Back to Top](#table-of-contents)**
12. ### What is a first order function
First-order function is a function that doesn’t accept another function as an argument and doesn’t return a function as its return value.
```javascript
const firstOrder = () => console.log("I am a first order function!");
```
**[⬆ Back to Top](#table-of-contents)**
13. ### What is a higher order function
Higher-order function is a function that accepts another function as an argument or returns a function as a return value or both.
```javascript
const firstOrderFunc = () =>
console.log("Hello, I am a First order function");
const higherOrder = (ReturnFirstOrderFunc) => ReturnFirstOrderFunc();
higherOrder(firstOrderFunc);
```
**[⬆ Back to Top](#table-of-contents)**
14. ### What is a unary function
Unary function (i.e. monadic) is a function that accepts exactly one argument. It stands for a single argument accepted by a function.
Let us take an example of unary function,
```javascript
const unaryFunction = (a) => console.log(a + 10); // Add 10 to the given argument and display the value
```
**[⬆ Back to Top](#table-of-contents)**
15. ### What is the currying function
Currying is the process of taking a function with multiple arguments and turning it into a sequence of functions each with only a single argument. Currying is named after a mathematician **Haskell Curry**. By applying currying, a n-ary function turns it into a unary function.
Let's take an example of n-ary function and how it turns into a currying function,
```javascript
const multiArgFunction = (a, b, c) => a + b + c;
console.log(multiArgFunction(1, 2, 3)); // 6
const curryUnaryFunction = (a) => (b) => (c) => a + b + c;
curryUnaryFunction(1); // returns a function: b => c => 1 + b + c
curryUnaryFunction(1)(2); // returns a function: c => 3 + c
curryUnaryFunction(1)(2)(3); // returns the number 6
```
Curried functions are great to improve **code reusability** and **functional composition**.
**[⬆ Back to Top](#table-of-contents)**
16. ### What is a pure function
A **Pure function** is a function where the return value is only determined by its arguments without any side effects. i.e, If you call a function with the same arguments 'n' number of times and 'n' number of places in the application then it will always return the same value.
Let's take an example to see the difference between pure and impure functions,
```javascript
//Impure
let numberArray = [];
const impureAddNumber = (number) => numberArray.push(number);
//Pure
const pureAddNumber = (number) => (argNumberArray) =>
argNumberArray.concat([number]);
//Display the results
console.log(impureAddNumber(6)); // returns 1
console.log(numberArray); // returns [6]
console.log(pureAddNumber(7)(numberArray)); // returns [6, 7]
console.log(numberArray); // returns [6]
```
As per the above code snippets, the **Push** function is impure itself by altering the array and returning a push number index independent of the parameter value. . Whereas **Concat** on the other hand takes the array and concatenates it with the other array producing a whole new array without side effects. Also, the return value is a concatenation of the previous array.
Remember that Pure functions are important as they simplify unit testing without any side effects and no need for dependency injection. They also avoid tight coupling and make it harder to break your application by not having any side effects. These principles are coming together with **Immutability** concept of ES6 by giving preference to **const** over **let** usage.
**[⬆ Back to Top](#table-of-contents)**
17. ### What is the purpose of the let keyword
The `let` statement declares a **block scope local variable**. Hence the variables defined with let keyword are limited in scope to the block, statement, or expression on which it is used. Whereas variables declared with the `var` keyword used to define a variable globally, or locally to an entire function regardless of block scope.
Let's take an example to demonstrate the usage,
```javascript
let counter = 30;
if (counter === 30) {
let counter = 31;
console.log(counter); // 31
}
console.log(counter); // 30 (because the variable in if block won't exist here)
```
**[⬆ Back to Top](#table-of-contents)**
18. ### What is the difference between let and var
You can list out the differences in a tabular format
| var | let |
| ----------------------------------------------------- | --------------------------- |
| It is been available from the beginning of JavaScript | Introduced as part of ES6 |
| It has function scope | It has block scope |
| Variables will be hoisted | Hoisted but not initialized |
Let's take an example to see the difference,
```javascript
function userDetails(username) {
if (username) {
console.log(salary); // undefined due to hoisting
console.log(age); // ReferenceError: Cannot access 'age' before initialization
let age = 30;
var salary = 10000;
}
console.log(salary); //10000 (accessible due to function scope)
console.log(age); //error: age is not defined(due to block scope)
}
userDetails("John");
```
**[⬆ Back to Top](#table-of-contents)**
19. ### What is the reason to choose the name let as a keyword
`let` is a mathematical statement that was adopted by early programming languages like **Scheme** and **Basic**. It has been borrowed from dozens of other languages that use `let` already as a traditional keyword as close to `var` as possible.
**[⬆ Back to Top](#table-of-contents)**
20. ### How do you redeclare variables in switch block without an error
If you try to redeclare variables in a `switch block` then it will cause errors because there is only one block. For example, the below code block throws a syntax error as below,
```javascript
let counter = 1;
switch (x) {
case 0:
let name;
break;
case 1:
let name; // SyntaxError for redeclaration.
break;
}
```
To avoid this error, you can create a nested block inside a case clause and create a new block scoped lexical environment.
```javascript
let counter = 1;
switch (x) {
case 0: {
let name;
break;
}
case 1: {
let name; // No SyntaxError for redeclaration.
break;
}
}
```
**[⬆ Back to Top](#table-of-contents)**
21. ### What is the Temporal Dead Zone
The Temporal Dead Zone is a behavior in JavaScript that occurs when declaring a variable with the let and const keywords, but not with var. In ECMAScript 6, accessing a `let` or `const` variable before its declaration (within its scope) causes a ReferenceError. The time span when that happens, between the creation of a variable’s binding and its declaration, is called the temporal dead zone.
Let's see this behavior with an example,
```javascript
function somemethod() {
console.log(counter1); // undefined
console.log(counter2); // ReferenceError
var counter1 = 1;
let counter2 = 2;
}
```
**[⬆ Back to Top](#table-of-contents)**
22. ### What is IIFE(Immediately Invoked Function Expression)
IIFE (Immediately Invoked Function Expression) is a JavaScript function that runs as soon as it is defined. The signature of it would be as below,
```javascript
(function () {
// logic here
})();
```
The primary reason to use an IIFE is to obtain data privacy because any variables declared within the IIFE cannot be accessed by the outside world. i.e, If you try to access variables with IIFE then it throws an error as below,
```javascript
(function () {
var message = "IIFE";
console.log(message);
})();
console.log(message); //Error: message is not defined
```
**[⬆ Back to Top](#table-of-contents)**
23. ### How do you decode or encode a URL in JavaScript?
`encodeURI()` function is used to encode an URL. This function requires a URL string as a parameter and return that encoded string.
`decodeURI()` function is used to decode an URL. This function requires an encoded URL string as parameter and return that decoded string.
**Note:** If you want to encode characters such as `/ ? : @ & = + $ #` then you need to use `encodeURIComponent()`.
```javascript
let uri = "employeeDetails?name=john&occupation=manager";
let encoded_uri = encodeURI(uri);
let decoded_uri = decodeURI(encoded_uri);
```
**[⬆ Back to Top](#table-of-contents)**
24. ### What is memoization
Memoization is a programming technique which attempts to increase a function’s performance by caching its previously computed results. Each time a memoized function is called, its parameters are used to index the cache. If the data is present, then it can be returned, without executing the entire function. Otherwise the function is executed and then the result is added to the cache.
Let's take an example of adding function with memoization,
```javascript
const memoizAddition = () => {
let cache = {};
return (value) => {
if (value in cache) {
console.log("Fetching from cache");
return cache[value]; // Here, cache.value cannot be used as property name starts with the number which is not a valid JavaScript identifier. Hence, can only be accessed using the square bracket notation.
} else {
console.log("Calculating result");
let result = value + 20;
cache[value] = result;
return result;
}
};
};
// returned function from memoizAddition
const addition = memoizAddition();
console.log(addition(20)); //output: 40 calculated
console.log(addition(20)); //output: 40 cached
```
**[⬆ Back to Top](#table-of-contents)**
25. ### What is Hoisting
Hoisting is a JavaScript mechanism where variables, function declarations and classes are moved to the top of their scope before code execution. Remember that JavaScript only hoists declarations, not initialisation.
Let's take a simple example of variable hoisting,
```javascript
console.log(message); //output : undefined
var message = "The variable Has been hoisted";
```
The above code looks like as below to the interpreter,
```javascript
var message;
console.log(message);
message = "The variable Has been hoisted";
```
In the same fashion, function declarations are hoisted too
```javascript
message("Good morning"); //Good morning
function message(name) {
console.log(name);
}
```
This hoisting makes functions to be safely used in code before they are declared.
**[⬆ Back to Top](#table-of-contents)**
26. ### What are classes in ES6
In ES6, Javascript classes are primarily syntactic sugar over JavaScript’s existing prototype-based inheritance.
For example, the prototype based inheritance written in function expression as below,
```javascript
function Bike(model, color) {
this.model = model;
this.color = color;
}
Bike.prototype.getDetails = function () {
return this.model + " bike has" + this.color + " color";
};
```
Whereas ES6 classes can be defined as an alternative
```javascript
class Bike {
constructor(color, model) {
this.color = color;
this.model = model;
}
getDetails() {
return this.model + " bike has" + this.color + " color";
}
}
```
**[⬆ Back to Top](#table-of-contents)**
27. ### What are closures
A closure is the combination of a function and the lexical environment within which that function was declared. i.e, It is an inner function that has access to the outer or enclosing function’s variables. The closure has three scope chains
1. Own scope where variables defined between its curly brackets
2. Outer function’s variables
3. Global variables
Let's take an example of closure concept,
```javascript
function Welcome(name) {
var greetingInfo = function (message) {
console.log(message + " " + name);
};
return greetingInfo;
}
var myFunction = Welcome("John");
myFunction("Welcome "); //Output: Welcome John
myFunction("Hello Mr."); //output: Hello Mr.John
```
As per the above code, the inner function(i.e, greetingInfo) has access to the variables in the outer function scope(i.e, Welcome) even after the outer function has returned.
**[⬆ Back to Top](#table-of-contents)**
28. ### What are modules
Modules refer to small units of independent, reusable code and also act as the foundation of many JavaScript design patterns. Most of the JavaScript modules export an object literal, a function, or a constructor
**[⬆ Back to Top](#table-of-contents)**
29. ### Why do you need modules
Below are the list of benefits using modules in javascript ecosystem
1. Maintainability
2. Reusability
3. Namespacing
**[⬆ Back to Top](#table-of-contents)**
30. ### What is scope in javascript
Scope is the accessibility of variables, functions, and objects in some particular part of your code during runtime. In other words, scope determines the visibility of variables and other resources in areas of your code.
**[⬆ Back to Top](#table-of-contents)**
31. ### What is a service worker
A Service worker is basically a script (JavaScript file) that runs in the background, separate from a web page and provides features that don't need a web page or user interaction. Some of the major features of service workers are Rich offline experiences(offline first web application development), periodic background syncs, push notifications, intercept and handle network requests and programmatically managing a cache of responses.
**[⬆ Back to Top](#table-of-contents)**
32. ### How do you manipulate DOM using a service worker
Service worker can't access the DOM directly. But it can communicate with the pages it controls by responding to messages sent via the `postMessage` interface, and those pages can manipulate the DOM.
**[⬆ Back to Top](#table-of-contents)**
33. ### How do you reuse information across service worker restarts
The problem with service worker is that it gets terminated when not in use, and restarted when it's next needed, so you cannot rely on global state within a service worker's `onfetch` and `onmessage` handlers. In this case, service workers will have access to IndexedDB API in order to persist and reuse across restarts.
**[⬆ Back to Top](#table-of-contents)**
34. ### What is IndexedDB
IndexedDB is a low-level API for client-side storage of larger amounts of structured data, including files/blobs. This API uses indexes to enable high-performance searches of this data.
**[⬆ Back to Top](#table-of-contents)**
35. ### What is web storage
Web storage is an API that provides a mechanism by which browsers can store key/value pairs locally within the user's browser, in a much more intuitive fashion than using cookies. The web storage provides two mechanisms for storing data on the client.
1. **Local storage:** It stores data for current origin with no expiration date.
2. **Session storage:** It stores data for one session and the data is lost when the browser tab is closed.
**[⬆ Back to Top](#table-of-contents)**
36. ### What is a post message
Post message is a method that enables cross-origin communication between Window objects.(i.e, between a page and a pop-up that it spawned, or between a page and an iframe embedded within it). Generally, scripts on different pages are allowed to access each other if and only if the pages follow same-origin policy(i.e, pages share the same protocol, port number, and host).
**[⬆ Back to Top](#table-of-contents)**
37. ### What is a Cookie
A cookie is a piece of data that is stored on your computer to be accessed by your browser. Cookies are saved as key/value pairs.
For example, you can create a cookie named username as below,
```javascript
document.cookie = "username=John";
```
**[⬆ Back to Top](#table-of-contents)**
38. ### Why do you need a Cookie
Cookies are used to remember information about the user profile(such as username). It basically involves two steps,
1. When a user visits a web page, the user profile can be stored in a cookie.
2. Next time the user visits the page, the cookie remembers the user profile.
**[⬆ Back to Top](#table-of-contents)**
39. ### What are the options in a cookie
There are few below options available for a cookie,
1. By default, the cookie is deleted when the browser is closed but you can change this behavior by setting expiry date (in UTC time).
```javascript
document.cookie = "username=John; expires=Sat, 8 Jun 2019 12:00:00 UTC";
```
1. By default, the cookie belongs to a current page. But you can tell the browser what path the cookie belongs to using a path parameter.
```javascript
document.cookie = "username=John; path=/services";
```
**[⬆ Back to Top](#table-of-contents)**
40. ### How do you delete a cookie
You can delete a cookie by setting the expiry date as a passed date. You don't need to specify a cookie value in this case.
For example, you can delete a username cookie in the current page as below.
```javascript
document.cookie =
"username=; expires=Fri, 07 Jun 2019 00:00:00 UTC; path=/;";
```
**Note:** You should define the cookie path option to ensure that you delete the right cookie. Some browsers doesn't allow to delete a cookie unless you specify a path parameter.
**[⬆ Back to Top](#table-of-contents)**
41. ### What are the differences between cookie, local storage and session storage
Below are some of the differences between cookie, local storage and session storage,
| Feature | Cookie | Local storage | Session storage |
| --------------------------------- | ---------------------------------- | ---------------- | ------------------- |
| Accessed on client or server side | Both server-side & client-side | client-side only | client-side only |
| Lifetime | As configured using Expires option | until deleted | until tab is closed |
| SSL support | Supported | Not supported | Not supported |
| Maximum data size | 4KB | 5 MB | 5MB |
**[⬆ Back to Top](#table-of-contents)**
42. ### What is the main difference between localStorage and sessionStorage
LocalStorage is the same as SessionStorage but it persists the data even when the browser is closed and reopened(i.e it has no expiration time) whereas in sessionStorage data gets cleared when the page session ends.
**[⬆ Back to Top](#table-of-contents)**
43. ### How do you access web storage
The Window object implements the `WindowLocalStorage` and `WindowSessionStorage` objects which has `localStorage`(window.localStorage) and `sessionStorage`(window.sessionStorage) properties respectively. These properties create an instance of the Storage object, through which data items can be set, retrieved and removed for a specific domain and storage type (session or local).
For example, you can read and write on local storage objects as below
```javascript
localStorage.setItem("logo", document.getElementById("logo").value);
localStorage.getItem("logo");
```
**[⬆ Back to Top](#table-of-contents)**
44. ### What are the methods available on session storage
The session storage provided methods for reading, writing and clearing the session data
```javascript
// Save data to sessionStorage
sessionStorage.setItem("key", "value");
// Get saved data from sessionStorage
let data = sessionStorage.getItem("key");
// Remove saved data from sessionStorage
sessionStorage.removeItem("key");
// Remove all saved data from sessionStorage
sessionStorage.clear();
```
**[⬆ Back to Top](#table-of-contents)**
45. ### What is a storage event and its event handler
The StorageEvent is an event that fires when a storage area has been changed in the context of another document. Whereas onstorage property is an EventHandler for processing storage events.
The syntax would be as below
```javascript
window.onstorage = functionRef;
```
Let's take the example usage of onstorage event handler which logs the storage key and it's values
```javascript
window.onstorage = function (e) {
console.log(
"The " +
e.key +
" key has been changed from " +
e.oldValue +
" to " +
e.newValue +
"."
);
};
```
**[⬆ Back to Top](#table-of-contents)**
46. ### Why do you need web storage
Web storage is more secure, and large amounts of data can be stored locally, without affecting website performance. Also, the information is never transferred to the server. Hence this is a more recommended approach than Cookies.
**[⬆ Back to Top](#table-of-contents)**
47. ### How do you check web storage browser support
You need to check browser support for localStorage and sessionStorage before using web storage,
```javascript
if (typeof Storage !== "undefined") {
// Code for localStorage/sessionStorage.
} else {
// Sorry! No Web Storage support..
}
```
**[⬆ Back to Top](#table-of-contents)**
48. ### How do you check web workers browser support
You need to check browser support for web workers before using it
```javascript
if (typeof Worker !== "undefined") {
// code for Web worker support.
} else {
// Sorry! No Web Worker support..
}
```
**[⬆ Back to Top](#table-of-contents)**
49. ### Give an example of a web worker
You need to follow below steps to start using web workers for counting example
1. Create a Web Worker File: You need to write a script to increment the count value. Let's name it as counter.js
```javascript
let i = 0;
function timedCount() {
i = i + 1;
postMessage(i);
setTimeout("timedCount()", 500);
}
timedCount();
```
Here postMessage() method is used to post a message back to the HTML page
1. Create a Web Worker Object: You can create a web worker object by checking for browser support. Let's name this file as web_worker_example.js
```javascript
if (typeof w == "undefined") {
w = new Worker("counter.js");
}
```
and we can receive messages from web worker
```javascript
w.onmessage = function (event) {
document.getElementById("message").innerHTML = event.data;
};
```
1. Terminate a Web Worker:
Web workers will continue to listen for messages (even after the external script is finished) until it is terminated. You can use the terminate() method to terminate listening to the messages.
```javascript
w.terminate();
```
1. Reuse the Web Worker: If you set the worker variable to undefined you can reuse the code
```javascript
w = undefined;
```
**[⬆ Back to Top](#table-of-contents)**
50. ### What are the restrictions of web workers on DOM
WebWorkers don't have access to below javascript objects since they are defined in an external files
1. Window object
2. Document object
3. Parent object
**[⬆ Back to Top](#table-of-contents)**
51. ### What is a promise
A promise is an object that may produce a single value some time in the future with either a resolved value or a reason that it’s not resolved(for example, network error). It will be in one of the 3 possible states: fulfilled, rejected, or pending.
The syntax of Promise creation looks like below,
```javascript
const promise = new Promise(function (resolve, reject) {
// promise description
});
```
The usage of a promise would be as below,
```javascript
const promise = new Promise(
(resolve) => {
setTimeout(() => {
resolve("I'm a Promise!");
}, 5000);
},
(reject) => {}
);
promise.then((value) => console.log(value));
```
The action flow of a promise will be as below,
**[⬆ Back to Top](#table-of-contents)**
52. ### Why do you need a promise
Promises are used to handle asynchronous operations. They provide an alternative approach for callbacks by reducing the callback hell and writing the cleaner code.
**[⬆ Back to Top](#table-of-contents)**
53. ### What are the three states of promise
Promises have three states:
1. **Pending:** This is an initial state of the Promise before an operation begins
2. **Fulfilled:** This state indicates that the specified operation was completed.
3. **Rejected:** This state indicates that the operation did not complete. In this case an error value will be thrown.
**[⬆ Back to Top](#table-of-contents)**
54. ### What is a callback function
A callback function is a function passed into another function as an argument. This function is invoked inside the outer function to complete an action.
Let's take a simple example of how to use callback function
```javascript
function callbackFunction(name) {
console.log("Hello " + name);
}
function outerFunction(callback) {
let name = prompt("Please enter your name.");
callback(name);
}
outerFunction(callbackFunction);
```
**[⬆ Back to Top](#table-of-contents)**
55. ### Why do we need callbacks
The callbacks are needed because javascript is an event driven language. That means instead of waiting for a response javascript will keep executing while listening for other events.
Let's take an example with the first function invoking an API call(simulated by setTimeout) and the next function which logs the message.
```javascript
function firstFunction() {
// Simulate a code delay
setTimeout(function () {
console.log("First function called");
}, 1000);
}
function secondFunction() {
console.log("Second function called");
}
firstFunction();
secondFunction();
Output;
// Second function called
// First function called
```
As observed from the output, javascript didn't wait for the response of the first function and the remaining code block got executed. So callbacks are used in a way to make sure that certain code doesn’t execute until the other code finishes execution.
**[⬆ Back to Top](#table-of-contents)**
56. ### What is a callback hell
Callback Hell is an anti-pattern with multiple nested callbacks which makes code hard to read and debug when dealing with asynchronous logic. The callback hell looks like below,
```javascript
async1(function(){
async2(function(){
async3(function(){
async4(function(){
....
});
});
});
});
```
**[⬆ Back to Top](#table-of-contents)**
57. ### What are server-sent events
Server-sent events (SSE) is a server push technology enabling a browser to receive automatic updates from a server via HTTP connection without resorting to polling. These are a one way communications channel - events flow from server to client only. This has been used in Facebook/Twitter updates, stock price updates, news feeds etc.
**[⬆ Back to Top](#table-of-contents)**
58. ### How do you receive server-sent event notifications
The EventSource object is used to receive server-sent event notifications. For example, you can receive messages from server as below,
```javascript
if (typeof EventSource !== "undefined") {
var source = new EventSource("sse_generator.js");
source.onmessage = function (event) {
document.getElementById("output").innerHTML += event.data + "<br>";
};
}
```
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59. ### How do you check browser support for server-sent events
You can perform browser support for server-sent events before using it as below,
```javascript
if (typeof EventSource !== "undefined") {
// Server-sent events supported. Let's have some code here!
} else {
// No server-sent events supported
}
```
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60. ### What are the events available for server sent events
Below are the list of events available for server sent events
| Event | Description |
|---- | ---------
| onopen | It is used when a connection to the server is opened |
| onmessage | This event is used when a message is received |
| onerror | It happens when an error occurs|
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61. ### What are the main rules of promise
A promise must follow a specific set of rules:
1. A promise is an object that supplies a standard-compliant `.then()` method
2. A pending promise may transition into either fulfilled or rejected state
3. A fulfilled or rejected promise is settled and it must not transition into any other state.
4. Once a promise is settled, the value must not change.
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62. ### What is callback in callback
You can nest one callback inside in another callback to execute the actions sequentially one by one. This is known as callbacks in callbacks.
```javascript
loadScript("/script1.js", function (script) {
console.log("first script is loaded");
loadScript("/script2.js", function (script) {
console.log("second script is loaded");
loadScript("/script3.js", function (script) {
console.log("third script is loaded");
// after all scripts are loaded
});
});
});
```
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63. ### What is promise chaining
The process of executing a sequence of asynchronous tasks one after another using promises is known as Promise chaining. Let's take an example of promise chaining for calculating the final result,
```javascript
new Promise(function (resolve, reject) {
setTimeout(() => resolve(1), 1000);
})
.then(function (result) {
console.log(result); // 1
return result * 2;
})
.then(function (result) {
console.log(result); // 2
return result * 3;
})
.then(function (result) {
console.log(result); // 6
return result * 4;
});
```
In the above handlers, the result is passed to the chain of .then() handlers with the below work flow,
1. The initial promise resolves in 1 second,
2. After that `.then` handler is called by logging the result(1) and then return a promise with the value of result \* 2.
3. After that the value passed to the next `.then` handler by logging the result(2) and return a promise with result \* 3.
4. Finally the value passed to the last `.then` handler by logging the result(6) and return a promise with result \* 4.
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64. ### What is promise.all
Promise.all is a promise that takes an array of promises as an input (an iterable), and it gets resolved when all the promises get resolved or any one of them gets rejected. For example, the syntax of promise.all method is below,
```javascript
Promise.all([Promise1, Promise2, Promise3]) .then(result) => { console.log(result) }) .catch(error => console.log(`Error in promises ${error}`))
```
**Note:** Remember that the order of the promises(output the result) is maintained as per input order.
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65. ### What is the purpose of the race method in promise
Promise.race() method will return the promise instance which is firstly resolved or rejected. Let's take an example of race() method where promise2 is resolved first
```javascript
var promise1 = new Promise(function (resolve, reject) {
setTimeout(resolve, 500, "one");
});
var promise2 = new Promise(function (resolve, reject) {
setTimeout(resolve, 100, "two");
});
Promise.race([promise1, promise2]).then(function (value) {
console.log(value); // "two" // Both promises will resolve, but promise2 is faster
});
```
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66. ### What is a strict mode in javascript
Strict Mode is a new feature in ECMAScript 5 that allows you to place a program, or a function, in a “strict” operating context. This way it prevents certain actions from being taken and throws more exceptions. The literal expression `"use strict";` instructs the browser to use the javascript code in the Strict mode.
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67. ### Why do you need strict mode
Strict mode is useful to write "secure" JavaScript by notifying "bad syntax" into real errors. For example, it eliminates accidentally creating a global variable by throwing an error and also throws an error for assignment to a non-writable property, a getter-only property, a non-existing property, a non-existing variable, or a non-existing object.
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68. ### How do you declare strict mode
The strict mode is declared by adding "use strict"; to the beginning of a script or a function.
If declared at the beginning of a script, it has global scope.
```javascript
"use strict";
x = 3.14; // This will cause an error because x is not declared
```
and if you declare inside a function, it has local scope
```javascript
x = 3.14; // This will not cause an error.
myFunction();
function myFunction() {
"use strict";
y = 3.14; // This will cause an error
}
```
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69. ### What is the purpose of double exclamation
The double exclamation or negation(!!) ensures the resulting type is a boolean. If it was falsey (e.g. 0, null, undefined, etc.), it will be false, otherwise, it will be true.
For example, you can test IE version using this expression as below,
```javascript
let isIE8 = false;
isIE8 = !!navigator.userAgent.match(/MSIE 8.0/);
console.log(isIE8); // returns true or false
```
If you don't use this expression then it returns the original value.
```javascript
console.log(navigator.userAgent.match(/MSIE 8.0/)); // returns either an Array or null
```
**Note:** The expression !! is not an operator, but it is just twice of ! operator.
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70. ### What is the purpose of the delete operator
The delete keyword is used to delete the property as well as its value.
```javascript
var user = { name: "John", age: 20 };
delete user.age;
console.log(user); // {name: "John"}
```
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71. ### What is typeof operator
You can use the JavaScript typeof operator to find the type of a JavaScript variable. It returns the type of a variable or an expression.
```javascript
typeof "John Abraham"; // Returns "string"
typeof (1 + 2); // Returns "number"
typeof [1, 2, 3] // Returns "object" because all arrays are also objects
```
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72. ### What is undefined property
The undefined property indicates that a variable has not been assigned a value, or declared but not initialized at all. The type of undefined value is undefined too.
```javascript
var user; // Value is undefined, type is undefined
console.log(typeof user); //undefined
```
Any variable can be emptied by setting the value to undefined.
```javascript
user = undefined;
```
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73. ### What is null value
The value null represents the intentional absence of any object value. It is one of JavaScript's primitive values. The type of null value is object.
You can empty the variable by setting the value to null.
```javascript
var user = null;
console.log(typeof user); //object
```
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74. ### What is the difference between null and undefined
Below are the main differences between null and undefined,
| Null | Undefined |
| ----------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------- |
| It is an assignment value which indicates that variable points to no object. | It is not an assignment value where a variable has been declared but has not yet been assigned a value. |
| Type of null is object | Type of undefined is undefined |
| The null value is a primitive value that represents the null, empty, or non-existent reference. | The undefined value is a primitive value used when a variable has not been assigned a value. |
| Indicates the absence of a value for a variable | Indicates absence of variable itself |
| Converted to zero (0) while performing primitive operations | Converted to NaN while performing primitive operations |
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75. ### What is eval
The eval() function evaluates JavaScript code represented as a string. The string can be a JavaScript expression, variable, statement, or sequence of statements.
```javascript
console.log(eval("1 + 2")); // 3
```
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76. ### What is the difference between window and document
Below are the main differences between window and document,
| Window | Document |
| ----------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------- |
| It is the root level element in any web page | It is the direct child of the window object. This is also known as Document Object Model(DOM) |
| By default window object is available implicitly in the page | You can access it via window.document or document. |
| It has methods like alert(), confirm() and properties like document, location | It provides methods like getElementById, getElementsByTagName, createElement etc |
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77. ### How do you access history in javascript
The window.history object contains the browser's history. You can load previous and next URLs in the history using back() and next() methods.
```javascript
function goBack() {
window.history.back();
}
function goForward() {
window.history.forward();
}
```
**Note:** You can also access history without window prefix.
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78. ### How do you detect caps lock key turned on or not
The `mouseEvent getModifierState()` is used to return a boolean value that indicates whether the specified modifier key is activated or not. The modifiers such as CapsLock, ScrollLock and NumLock are activated when they are clicked, and deactivated when they are clicked again.
Let's take an input element to detect the CapsLock on/off behavior with an example,
```html
<input type="password" onmousedown="enterInput(event)" />
<p id="feedback"></p>
<script>
function enterInput(e) {
var flag = e.getModifierState("CapsLock");
if (flag) {
document.getElementById("feedback").innerHTML = "CapsLock activated";
} else {
document.getElementById("feedback").innerHTML =
"CapsLock not activated";
}
}
</script>
```
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79. ### What is isNaN
The isNaN() function is used to determine whether a value is an illegal number (Not-a-Number) or not. i.e, This function returns true if the value equates to NaN. Otherwise it returns false.
```javascript
isNaN("Hello"); //true
isNaN("100"); //false
```
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80. ### What are the differences between undeclared and undefined variables
Below are the major differences between undeclared(not defined) and undefined variables,
| undeclared | undefined |
| ------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------- |
| These variables do not exist in a program and are not declared | These variables declared in the program but have not assigned any value |
| If you try to read the value of an undeclared variable, then a runtime error is encountered | If you try to read the value of an undefined variable, an undefined value is returned. |
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81. ### What are global variables
Global variables are those that are available throughout the length of the code without any scope. The var keyword is used to declare a local variable but if you omit it then it will become global variable
```javascript
msg = "Hello"; // var is missing, it becomes global variable
```
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82. ### What are the problems with global variables
The problem with global variables is the conflict of variable names of local and global scope. It is also difficult to debug and test the code that relies on global variables.
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83. ### What is NaN property
The NaN property is a global property that represents "Not-a-Number" value. i.e, It indicates that a value is not a legal number. It is very rare to use NaN in a program but it can be used as return value for few cases
```javascript
Math.sqrt(-1);
parseInt("Hello");
```
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84. ### What is the purpose of isFinite function
The isFinite() function is used to determine whether a number is a finite, legal number. It returns false if the value is +infinity, -infinity, or NaN (Not-a-Number), otherwise it returns true.
```javascript
isFinite(Infinity); // false
isFinite(NaN); // false
isFinite(-Infinity); // false
isFinite(100); // true
```
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85. ### What is an event flow
Event flow is the order in which event is received on the web page. When you click an element that is nested in various other elements, before your click actually reaches its destination, or target element, it must trigger the click event for each of its parent elements first, starting at the top with the global window object.
There are two ways of event flow
1. Top to Bottom(Event Capturing)
2. Bottom to Top (Event Bubbling)
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86. ### What is event bubbling
Event bubbling is a type of event propagation where the event first triggers on the innermost target element, and then successively triggers on the ancestors (parents) of the target element in the same nesting hierarchy till it reaches the outermost DOM element.
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87. ### What is event capturing
Event capturing is a type of event propagation where the event is first captured by the outermost element, and then successively triggers on the descendants (children) of the target element in the same nesting hierarchy till it reaches the innermost DOM element.
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88. ### How do you submit a form using JavaScript
You can submit a form using `document.forms[0].submit()`. All the form input's information is submitted using onsubmit event handler
```javascript
function submit() {
document.forms[0].submit();
}
```
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89. ### How do you find operating system details
The window.navigator object contains information about the visitor's browser OS details. Some of the OS properties are available under platform property,
```javascript
console.log(navigator.platform);
```
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90. ### What is the difference between document load and DOMContentLoaded events
The `DOMContentLoaded` event is fired when the initial HTML document has been completely loaded and parsed, without waiting for assets(stylesheets, images, and subframes) to finish loading. Whereas The load event is fired when the whole page has loaded, including all dependent resources(stylesheets, images).
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91. ### What is the difference between native, host and user objects
`Native objects` are objects that are part of the JavaScript language defined by the ECMAScript specification. For example, String, Math, RegExp, Object, Function etc core objects defined in the ECMAScript spec.
`Host objects` are objects provided by the browser or runtime environment (Node). For example, window, XmlHttpRequest, DOM nodes etc are considered as host objects.
`User objects` are objects defined in the javascript code. For example, User objects created for profile information.
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92. ### What are the tools or techniques used for debugging JavaScript code
You can use below tools or techniques for debugging javascript
1. Chrome Devtools
2. debugger statement
3. Good old console.log statement
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93. ### What are the pros and cons of promises over callbacks
Below are the list of pros and cons of promises over callbacks,
**Pros:**
1. It avoids callback hell which is unreadable
2. Easy to write sequential asynchronous code with .then()
3. Easy to write parallel asynchronous code with Promise.all()
4. Solves some of the common problems of callbacks(call the callback too late, too early, many times and swallow errors/exceptions)
**Cons:**
1. It makes little complex code
2. You need to load a polyfill if ES6 is not supported
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94. ### What is the difference between an attribute and a property
Attributes are defined on the HTML markup whereas properties are defined on the DOM. For example, the below HTML element has 2 attributes type and value,
```javascript
<input type="text" value="Name:">
```
You can retrieve the attribute value as below,
```javascript
const input = document.querySelector("input");
console.log(input.getAttribute("value")); // Good morning
console.log(input.value); // Good morning
```
And after you change the value of the text field to "Good evening", it becomes like
```javascript
console.log(input.getAttribute("value")); // Good evening
console.log(input.value); // Good evening
```
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95. ### What is same-origin policy
The same-origin policy is a policy that prevents JavaScript from making requests across domain boundaries. An origin is defined as a combination of URI scheme, hostname, and port number. If you enable this policy then it prevents a malicious script on one page from obtaining access to sensitive data on another web page using Document Object Model(DOM).
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96. ### What is the purpose of void 0
Void(0) is used to prevent the page from refreshing. This will be helpful to eliminate the unwanted side-effect, because it will return the undefined primitive value. It is commonly used for HTML documents that use href="JavaScript:Void(0);" within an `<a>` element. i.e, when you click a link, the browser loads a new page or refreshes the same page. But this behavior will be prevented using this expression.
For example, the below link notify the message without reloading the page
```javascript
<a href="JavaScript:void(0);" onclick="alert('Well done!')">
Click Me!
</a>
```
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97. ### Is JavaScript a compiled or interpreted language
JavaScript is an interpreted language, not a compiled language. An interpreter in the browser reads over the JavaScript code, interprets each line, and runs it. Nowadays modern browsers use a technology known as Just-In-Time (JIT) compilation, which compiles JavaScript to executable bytecode just as it is about to run.
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98. ### Is JavaScript a case-sensitive language
Yes, JavaScript is a case sensitive language. The language keywords, variables, function & object names, and any other identifiers must always be typed with a consistent capitalization of letters.
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99. ### Is there any relation between Java and JavaScript
No, they are entirely two different programming languages and have nothing to do with each other. But both of them are Object Oriented Programming languages and like many other languages, they follow similar syntax for basic features(if, else, for, switch, break, continue etc).
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100. ### What are events
Events are "things" that happen to HTML elements. When JavaScript is used in HTML pages, JavaScript can `react` on these events. Some of the examples of HTML events are,
1. Web page has finished loading
2. Input field was changed
3. Button was clicked
Let's describe the behavior of click event for button element,
```javascript
<!doctype html>
<html>
<head>
<script>
function greeting() {
alert('Hello! Good morning');
}
</script>
</head>
<body>
<button type="button" onclick="greeting()">Click me</button>
</body>
</html>
```
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101. ### Who created javascript
JavaScript was created by Brendan Eich in 1995 during his time at Netscape Communications. Initially it was developed under the name `Mocha`, but later the language was officially called `LiveScript` when it first shipped in beta releases of Netscape.
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102. ### What is the use of preventDefault method
The preventDefault() method cancels the event if it is cancelable, meaning that the default action or behaviour that belongs to the event will not occur. For example, prevent form submission when clicking on submit button and prevent opening the page URL when clicking on hyperlink are some common use cases.
```javascript
document
.getElementById("link")
.addEventListener("click", function (event) {
event.preventDefault();
});
```
**Note:** Remember that not all events are cancelable.
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103. ### What is the use of stopPropagation method
The stopPropagation method is used to stop the event from bubbling up the event chain. For example, the below nested divs with stopPropagation method prevents default event propagation when clicking on nested div(Div1)
```javascript
<p>Click DIV1 Element</p>
<div onclick="secondFunc()">DIV 2
<div onclick="firstFunc(event)">DIV 1</div>
</div>
<script>
function firstFunc(event) {
alert("DIV 1");
event.stopPropagation();
}
function secondFunc() {
alert("DIV 2");
}
</script>
```
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104. ### What are the steps involved in return false usage
The return false statement in event handlers performs the below steps,
1. First it stops the browser's default action or behaviour.
2. It prevents the event from propagating the DOM
3. Stops callback execution and returns immediately when called.
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105. ### What is BOM
The Browser Object Model (BOM) allows JavaScript to "talk to" the browser. It consists of the objects navigator, history, screen, location and document which are children of the window. The Browser Object Model is not standardized and can change based on different browsers.
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106. ### What is the use of setTimeout
The setTimeout() method is used to call a function or evaluate an expression after a specified number of milliseconds. For example, let's log a message after 2 seconds using setTimeout method,
```javascript
setTimeout(function () {
console.log("Good morning");
}, 2000);
```
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107. ### What is the use of setInterval
The setInterval() method is used to call a function or evaluate an expression at specified intervals (in milliseconds). For example, let's log a message after 2 seconds using setInterval method,
```javascript
setInterval(function () {
console.log("Good morning");
}, 2000);
```
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108. ### Why is JavaScript treated as Single threaded
JavaScript is a single-threaded language. Because the language specification does not allow the programmer to write code so that the interpreter can run parts of it in parallel in multiple threads or processes. Whereas languages like java, go, C++ can make multi-threaded and multi-process programs.
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109. ### What is an event delegation
Event delegation is a technique for listening to events where you delegate a parent element as the listener for all of the events that happen inside it.
For example, if you wanted to detect field changes in inside a specific form, you can use event delegation technique,
```javascript
var form = document.querySelector("#registration-form");
// Listen for changes to fields inside the form
form.addEventListener(
"input",
function (event) {
// Log the field that was changed
console.log(event.target);
},
false
);
```
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110. ### What is ECMAScript
ECMAScript is the scripting language that forms the basis of JavaScript. ECMAScript standardized by the ECMA International standards organization in the ECMA-262 and ECMA-402 specifications. The first edition of ECMAScript was released in 1997.
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111. ### What is JSON
JSON (JavaScript Object Notation) is a lightweight format that is used for data interchanging. It is based on a subset of JavaScript language in the way objects are built in JavaScript.
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112. ### What are the syntax rules of JSON
Below are the list of syntax rules of JSON
1. The data is in name/value pairs
2. The data is separated by commas
3. Curly braces hold objects
4. Square brackets hold arrays
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113. ### What is the purpose JSON stringify
When sending data to a web server, the data has to be in a string format. You can achieve this by converting JSON object into a string using stringify() method.
```javascript
var userJSON = { name: "John", age: 31 };
var userString = JSON.stringify(userJSON);
console.log(userString); //"{"name":"John","age":31}"
```
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114. ### How do you parse JSON string
When receiving the data from a web server, the data is always in a string format. But you can convert this string value to a javascript object using parse() method.
```javascript
var userString = '{"name":"John","age":31}';
var userJSON = JSON.parse(userString);
console.log(userJSON); // {name: "John", age: 31}
```
**[⬆ Back to Top](#table-of-contents)**
115. ### Why do you need JSON
When exchanging data between a browser and a server, the data can only be text. Since JSON is text only, it can easily be sent to and from a server, and used as a data format by any programming language.
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116. ### What are PWAs
Progressive web applications (PWAs) are a type of mobile app delivered through the web, built using common web technologies including HTML, CSS and JavaScript. These PWAs are deployed to servers, accessible through URLs, and indexed by search engines.
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117. ### What is the purpose of clearTimeout method
The clearTimeout() function is used in javascript to clear the timeout which has been set by setTimeout()function before that. i.e, The return value of setTimeout() function is stored in a variable and it’s passed into the clearTimeout() function to clear the timer.
For example, the below setTimeout method is used to display the message after 3 seconds. This timeout can be cleared by the clearTimeout() method.
```javascript
<script>
var msg;
function greeting() {
alert('Good morning');
}
function start() {
msg =setTimeout(greeting, 3000);
}
function stop() {
clearTimeout(msg);
}
</script>
```
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118. ### What is the purpose of clearInterval method
The clearInterval() function is used in javascript to clear the interval which has been set by setInterval() function. i.e, The return value returned by setInterval() function is stored in a variable and it’s passed into the clearInterval() function to clear the interval.
For example, the below setInterval method is used to display the message for every 3 seconds. This interval can be cleared by the clearInterval() method.
```javascript
<script>
var msg;
function greeting() {
alert('Good morning');
}
function start() {
msg = setInterval(greeting, 3000);
}
function stop() {
clearInterval(msg);
}
</script>
```
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119. ### How do you redirect new page in javascript
In vanilla javascript, you can redirect to a new page using the `location` property of window object. The syntax would be as follows,
```javascript
function redirect() {
window.location.href = "newPage.html";
}
```
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120. ### How do you check whether a string contains a substring
There are 3 possible ways to check whether a string contains a substring or not,
1. **Using includes:** ES6 provided `String.prototype.includes` method to test a string contains a substring
```javascript
var mainString = "hello",
subString = "hell";
mainString.includes(subString);
```
1. **Using indexOf:** In an ES5 or older environment, you can use `String.prototype.indexOf` which returns the index of a substring. If the index value is not equal to -1 then it means the substring exists in the main string.
```javascript
var mainString = "hello",
subString = "hell";
mainString.indexOf(subString) !== -1;
```
1. **Using RegEx:** The advanced solution is using Regular expression's test method(`RegExp.test`), which allows for testing for against regular expressions
```javascript
var mainString = "hello",
regex = /hell/;
regex.test(mainString);
```
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121. ### How do you validate an email in javascript
You can validate an email in javascript using regular expressions. It is recommended to do validations on the server side instead of the client side. Because the javascript can be disabled on the client side.
```javascript
function validateEmail(email) {
var re =
/^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
return re.test(String(email).toLowerCase());
}
```
**[⬆ Back to Top](#table-of-contents)**
The above regular expression accepts unicode characters.
122. ### How do you get the current url with javascript
You can use `window.location.href` expression to get the current url path and you can use the same expression for updating the URL too. You can also use `document.URL` for read-only purposes but this solution has issues in FF.
```javascript
console.log("location.href", window.location.href); // Returns full URL
```
**[⬆ Back to Top](#table-of-contents)**
123. ### What are the various url properties of location object
The below `Location` object properties can be used to access URL components of the page,
1. href - The entire URL
2. protocol - The protocol of the URL
3. host - The hostname and port of the URL
4. hostname - The hostname of the URL
5. port - The port number in the URL
6. pathname - The path name of the URL
7. search - The query portion of the URL
8. hash - The anchor portion of the URL
**[⬆ Back to Top](#table-of-contents)**
124. ### How do get query string values in javascript
You can use URLSearchParams to get query string values in javascript. Let's see an example to get the client code value from URL query string,
```javascript
const urlParams = new URLSearchParams(window.location.search);
const clientCode = urlParams.get("clientCode");
```
**[⬆ Back to Top](#table-of-contents)**
125. ### How do you check if a key exists in an object
You can check whether a key exists in an object or not using three approaches,
1. **Using in operator:** You can use the in operator whether a key exists in an object or not
```javascript
"key" in obj;
```
and If you want to check if a key doesn't exist, remember to use parenthesis,
```javascript
!("key" in obj);
```
1. **Using hasOwnProperty method:** You can use `hasOwnProperty` to particularly test for properties of the object instance (and not inherited properties)
```javascript
obj.hasOwnProperty("key"); // true
```
1. **Using undefined comparison:** If you access a non-existing property from an object, the result is undefined. Let’s compare the properties against undefined to determine the existence of the property.
```javascript
const user = {
name: "John",
};
console.log(user.name !== undefined); // true
console.log(user.nickName !== undefined); // false
```
**[⬆ Back to Top](#table-of-contents)**
126. ### How do you loop through or enumerate javascript object
You can use the `for-in` loop to loop through javascript object. You can also make sure that the key you get is an actual property of an object, and doesn't come from the prototype using `hasOwnProperty` method.
```javascript
var object = {
k1: "value1",
k2: "value2",
k3: "value3",
};
for (var key in object) {
if (object.hasOwnProperty(key)) {
console.log(key + " -> " + object[key]); // k1 -> value1 ...
}
}
```
**[⬆ Back to Top](#table-of-contents)**
127. ### How do you test for an empty object
There are different solutions based on ECMAScript versions
1. **Using Object entries(ECMA 7+):** You can use object entries length along with constructor type.
```javascript
Object.entries(obj).length === 0 && obj.constructor === Object; // Since date object length is 0, you need to check constructor check as well
```
1. **Using Object keys(ECMA 5+):** You can use object keys length along with constructor type.
```javascript
Object.keys(obj).length === 0 && obj.constructor === Object; // Since date object length is 0, you need to check constructor check as well
```
1. **Using for-in with hasOwnProperty(Pre-ECMA 5):** You can use a for-in loop along with hasOwnProperty.
```javascript
function isEmpty(obj) {
for (var prop in obj) {
if (obj.hasOwnProperty(prop)) {
return false;
}
}
return JSON.stringify(obj) === JSON.stringify({});
}
```
**[⬆ Back to Top](#table-of-contents)**
128. ### What is an arguments object
The arguments object is an Array-like object accessible inside functions that contains the values of the arguments passed to that function. For example, let's see how to use arguments object inside sum function,
```javascript
function sum() {
var total = 0;
for (var i = 0, len = arguments.length; i < len; ++i) {
total += arguments[i];
}
return total;
}
sum(1, 2, 3); // returns 6
```
**Note:** You can't apply array methods on arguments object. But you can convert into a regular array as below.
```javascript
var argsArray = Array.prototype.slice.call(arguments);
```
**[⬆ Back to Top](#table-of-contents)**
129. ### How do you make first letter of the string in an uppercase
You can create a function which uses a chain of string methods such as charAt, toUpperCase and slice methods to generate a string with the first letter in uppercase.
```javascript
function capitalizeFirstLetter(string) {
return string.charAt(0).toUpperCase() + string.slice(1);
}
```
**[⬆ Back to Top](#table-of-contents)**
130. ### What are the pros and cons of for loop
The for-loop is a commonly used iteration syntax in javascript. It has both pros and cons
#### Pros
1. Works on every environment
2. You can use break and continue flow control statements
#### Cons
1. Too verbose
2. Imperative
3. You might face one-by-off errors
**[⬆ Back to Top](#table-of-contents)**
131. ### How do you display the current date in javascript
You can use `new Date()` to generate a new Date object containing the current date and time. For example, let's display the current date in mm/dd/yyyy
```javascript
var today = new Date();
var dd = String(today.getDate()).padStart(2, "0");
var mm = String(today.getMonth() + 1).padStart(2, "0"); //January is 0!
var yyyy = today.getFullYear();
today = mm + "/" + dd + "/" + yyyy;
document.write(today);
```
**[⬆ Back to Top](#table-of-contents)**
132. ### How do you compare two date objects
You need to use date.getTime() method to compare date values instead of comparison operators (==, !=, ===, and !== operators)
```javascript
var d1 = new Date();
var d2 = new Date(d1);
console.log(d1.getTime() === d2.getTime()); //True
console.log(d1 === d2); // False
```
**[⬆ Back to Top](#table-of-contents)**
133. ### How do you check if a string starts with another string
You can use ECMAScript 6's `String.prototype.startsWith()` method to check if a string starts with another string or not. But it is not yet supported in all browsers. Let's see an example to see this usage,
```javascript
"Good morning".startsWith("Good"); // true
"Good morning".startsWith("morning"); // false
```
**[⬆ Back to Top](#table-of-contents)**
134. ### How do you trim a string in javascript
JavaScript provided a trim method on string types to trim any whitespaces present at the beginning or ending of the string.
```javascript
" Hello World ".trim(); //Hello World
```
If your browser(<IE9) doesn't support this method then you can use below polyfill.
```javascript
if (!String.prototype.trim) {
(function () {
// Make sure we trim BOM and NBSP
var rtrim = /^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/g;
String.prototype.trim = function () {
return this.replace(rtrim, "");
};
})();
}
```
**[⬆ Back to Top](#table-of-contents)**
135. ### How do you add a key value pair in javascript
There are two possible solutions to add new properties to an object. Let's take a simple object to explain these solutions.
```javascript
var object = {
key1: value1,
key2: value2,
};
```
1. **Using dot notation:** This solution is useful when you know the name of the property
```javascript
object.key3 = "value3";
```
1. **Using square bracket notation:** This solution is useful when the name of the property is dynamically determined.
```javascript
obj["key3"] = "value3";
```
**[⬆ Back to Top](#table-of-contents)**
136. ### Is the !-- notation represents a special operator
No,that's not a special operator. But it is a combination of 2 standard operators one after the other,
1. A logical not (!)
2. A prefix decrement (--)
At first, the value decremented by one and then tested to see if it is equal to zero or not for determining the truthy/falsy value.
**[⬆ Back to Top](#table-of-contents)**
137. ### How do you assign default values to variables
You can use the logical or operator `||` in an assignment expression to provide a default value. The syntax looks like as below,
```javascript
var a = b || c;
```
As per the above expression, variable 'a 'will get the value of 'c' only if 'b' is falsy (if is null, false, undefined, 0, empty string, or NaN), otherwise 'a' will get the value of 'b'.
**[⬆ Back to Top](#table-of-contents)**
138. ### How do you define multiline strings
You can define multiline string literals using the '\\' character followed by line terminator.
```javascript
var str =
"This is a \
very lengthy \
sentence!";
```
But if you have a space after the '\\' character, the code will look exactly the same, but it will raise a SyntaxError.
**[⬆ Back to Top](#table-of-contents)**
139. ### What is an app shell model
An application shell (or app shell) architecture is one way to build a Progressive Web App that reliably and instantly loads on your users' screens, similar to what you see in native applications. It is useful for getting some initial HTML to the screen fast without a network.
**[⬆ Back to Top](#table-of-contents)**
140. ### Can we define properties for functions
Yes, We can define properties for functions because functions are also objects.
```javascript
fn = function (x) {
//Function code goes here
};
fn.name = "John";
fn.profile = function (y) {
//Profile code goes here
};
```
**[⬆ Back to Top](#table-of-contents)**
141. ### What is the way to find the number of parameters expected by a function
You can use `function.length` syntax to find the number of parameters expected by a function. Let's take an example of `sum` function to calculate the sum of numbers,
```javascript
function sum(num1, num2, num3, num4) {
return num1 + num2 + num3 + num4;
}
sum.length; // 4 is the number of parameters expected.
```
**[⬆ Back to Top](#table-of-contents)**
142. ### What is a polyfill
A polyfill is a piece of JS code used to provide modern functionality on older browsers that do not natively support it. For example, Silverlight plugin polyfill can be used to mimic the functionality of an HTML Canvas element on Microsoft Internet Explorer 7.
**[⬆ Back to Top](#table-of-contents)**
143. ### What are break and continue statements
The break statement is used to "jump out" of a loop. i.e, It breaks the loop and continues executing the code after the loop.
```javascript
for (i = 0; i < 10; i++) {
if (i === 5) {
break;
}
text += "Number: " + i + "<br>";
}
```
The continue statement is used to "jump over" one iteration in the loop. i.e, It breaks one iteration (in the loop), if a specified condition occurs, and continues with the next iteration in the loop.
```javascript
for (i = 0; i < 10; i++) {
if (i === 5) {
continue;
}
text += "Number: " + i + "<br>";
}
```
**[⬆ Back to Top](#table-of-contents)**
144. ### What are js labels
The label statement allows us to name loops and blocks in JavaScript. We can then use these labels to refer back to the code later. For example, the below code with labels avoids printing the numbers when they are same,
```javascript
var i, j;
loop1: for (i = 0; i < 3; i++) {
loop2: for (j = 0; j < 3; j++) {
if (i === j) {
continue loop1;
}
console.log("i = " + i + ", j = " + j);
}
}
// Output is:
// "i = 1, j = 0"
// "i = 2, j = 0"
// "i = 2, j = 1"
```
**[⬆ Back to Top](#table-of-contents)**
145. ### What are the benefits of keeping declarations at the top
It is recommended to keep all declarations at the top of each script or function. The benefits of doing this are,
1. Gives cleaner code
2. It provides a single place to look for local variables
3. Easy to avoid unwanted global variables
4. It reduces the possibility of unwanted re-declarations
**[⬆ Back to Top](#table-of-contents)**
146. ### What are the benefits of initializing variables
It is recommended to initialize variables because of the below benefits,
1. It gives cleaner code
2. It provides a single place to initialize variables
3. Avoid undefined values in the code
**[⬆ Back to Top](#table-of-contents)**
147. ### What are the recommendations to create new object
It is recommended to avoid creating new objects using `new Object()`. Instead you can initialize values based on it's type to create the objects.
1. Assign {} instead of new Object()
2. Assign "" instead of new String()
3. Assign 0 instead of new Number()
4. Assign false instead of new Boolean()
5. Assign [] instead of new Array()
6. Assign /()/ instead of new RegExp()
7. Assign function (){} instead of new Function()
You can define them as an example,
```javascript
var v1 = {};
var v2 = "";
var v3 = 0;
var v4 = false;
var v5 = [];
var v6 = /()/;
var v7 = function () {};
```
**[⬆ Back to Top](#table-of-contents)**
148. ### How do you define JSON arrays
JSON arrays are written inside square brackets and arrays contain javascript objects. For example, the JSON array of users would be as below,
```javascript
"users":[
{"firstName":"John", "lastName":"Abrahm"},
{"firstName":"Anna", "lastName":"Smith"},
{"firstName":"Shane", "lastName":"Warn"}
]
```
**[⬆ Back to Top](#table-of-contents)**
149. ### How do you generate random integers
You can use Math.random() with Math.floor() to return random integers. For example, if you want generate random integers between 1 to 10, the multiplication factor should be 10,
```javascript
Math.floor(Math.random() * 10) + 1; // returns a random integer from 1 to 10
Math.floor(Math.random() * 100) + 1; // returns a random integer from 1 to 100
```
**Note:** Math.random() returns a random number between 0 (inclusive), and 1 (exclusive)
**[⬆ Back to Top](#table-of-contents)**
150. ### Can you write a random integers function to print integers with in a range
Yes, you can create a proper random function to return a random number between min and max (both included)
```javascript
function randomInteger(min, max) {
return Math.floor(Math.random() * (max - min + 1)) + min;
}
randomInteger(1, 100); // returns a random integer from 1 to 100
randomInteger(1, 1000); // returns a random integer from 1 to 1000
```
**[⬆ Back to Top](#table-of-contents)**
151. ### What is tree shaking
Tree shaking is a form of dead code elimination. It means that unused modules will not be included in the bundle during the build process and for that it relies on the static structure of ES2015 module syntax,( i.e. import and export). Initially this has been popularized by the ES2015 module bundler `rollup`.
**[⬆ Back to Top](#table-of-contents)**
152. ### What is the need of tree shaking
Tree Shaking can significantly reduce the code size in any application. i.e, The less code we send over the wire the more performant the application will be. For example, if we just want to create a “Hello World” Application using SPA frameworks then it will take around a few MBs, but by tree shaking it can bring down the size to just a few hundred KBs. Tree shaking is implemented in Rollup and Webpack bundlers.
**[⬆ Back to Top](#table-of-contents)**
153. ### Is it recommended to use eval
No, it allows arbitrary code to be run which causes a security problem. As we know that the eval() function is used to run text as code. In most of the cases, it should not be necessary to use it.
**[⬆ Back to Top](#table-of-contents)**
154. ### What is a Regular Expression
A regular expression is a sequence of characters that forms a search pattern. You can use this search pattern for searching data in a text. These can be used to perform all types of text search and text replace operations. Let's see the syntax format now,
```javascript
/pattern/modifiers;
```
For example, the regular expression or search pattern with case-insensitive username would be,
```javascript
/John/i;
```
**[⬆ Back to Top](#table-of-contents)**
155. ### What are the string methods available in Regular expression
Regular Expressions has two string methods: search() and replace().
The search() method uses an expression to search for a match, and returns the position of the match.
```javascript
var msg = "Hello John";
var n = msg.search(/John/i); // 6
```
The replace() method is used to return a modified string where the pattern is replaced.
```javascript
var msg = "Hello John";
var n = msg.replace(/John/i, "Buttler"); // Hello Buttler
```
**[⬆ Back to Top](#table-of-contents)**
156. ### What are modifiers in regular expression
Modifiers can be used to perform case-insensitive and global searches. Let's list down some of the modifiers,
| Modifier | Description |
| -------- | ------------------------------------------------------- |
| i | Perform case-insensitive matching |
| g | Perform a global match rather than stops at first match |
| m | Perform multiline matching |
Let's take an example of global modifier,
```javascript
var text = "Learn JS one by one";
var pattern = /one/g;
var result = text.match(pattern); // one,one
```
**[⬆ Back to Top](#table-of-contents)**
157. ### What are regular expression patterns
Regular Expressions provide a group of patterns in order to match characters. Basically they are categorized into 3 types,
1. **Brackets:** These are used to find a range of characters.
For example, below are some use cases,
1. [abc]: Used to find any of the characters between the brackets(a,b,c)
2. [0-9]: Used to find any of the digits between the brackets
3. (a|b): Used to find any of the alternatives separated with |
2. **Metacharacters:** These are characters with a special meaning
For example, below are some use cases,
1. \\d: Used to find a digit
2. \\s: Used to find a whitespace character
3. \\b: Used to find a match at the beginning or ending of a word
3. **Quantifiers:** These are useful to define quantities
For example, below are some use cases,
1. n+: Used to find matches for any string that contains at least one n
2. n\*: Used to find matches for any string that contains zero or more occurrences of n
3. n?: Used to find matches for any string that contains zero or one occurrences of n
**[⬆ Back to Top](#table-of-contents)**
158. ### What is a RegExp object
RegExp object is a regular expression object with predefined properties and methods. Let's see the simple usage of RegExp object,
```javascript
var regexp = new RegExp("\\w+");
console.log(regexp);
// expected output: /\w+/
```
**[⬆ Back to Top](#table-of-contents)**
159. ### How do you search a string for a pattern
You can use the test() method of regular expression in order to search a string for a pattern, and return true or false depending on the result.
```javascript
var pattern = /you/;
console.log(pattern.test("How are you?")); //true
```
**[⬆ Back to Top](#table-of-contents)**
160. ### What is the purpose of exec method
The purpose of exec method is similar to test method but it executes a search for a match in a specified string and returns a result array, or null instead of returning true/false.
```javascript
var pattern = /you/;
console.log(pattern.exec("How are you?")); //["you", index: 8, input: "How are you?", groups: undefined]
```
**[⬆ Back to Top](#table-of-contents)**
161. ### How do you change the style of a HTML element
You can change inline style or classname of a HTML element using javascript
1. **Using style property:** You can modify inline style using style property
```javascript
document.getElementById("title").style.fontSize = "30px";
```
1. **Using ClassName property:** It is easy to modify element class using className property
```javascript
document.getElementById("title").className = "custom-title";
```
**[⬆ Back to Top](#table-of-contents)**
162. ### What would be the result of 1+2+'3'
The output is going to be `33`. Since `1` and `2` are numeric values, the result of the first two digits is going to be a numeric value `3`. The next digit is a string type value because of that the addition of numeric value `3` and string type value `3` is just going to be a concatenation value `33`.
**[⬆ Back to Top](#table-of-contents)**
163. ### What is a debugger statement
The debugger statement invokes any available debugging functionality, such as setting a breakpoint. If no debugging functionality is available, this statement has no effect.
For example, in the below function a debugger statement has been inserted. So
execution is paused at the debugger statement just like a breakpoint in the script source.
```javascript
function getProfile() {
// code goes here
debugger;
// code goes here
}
```
**[⬆ Back to Top](#table-of-contents)**
164. ### What is the purpose of breakpoints in debugging
You can set breakpoints in the javascript code once the debugger statement is executed and the debugger window pops up. At each breakpoint, javascript will stop executing, and let you examine the JavaScript values. After examining values, you can resume the execution of code using the play button.
**[⬆ Back to Top](#table-of-contents)**
165. ### Can I use reserved words as identifiers
No, you cannot use the reserved words as variables, labels, object or function names. Let's see one simple example,
```javascript
var else = "hello"; // Uncaught SyntaxError: Unexpected token else
```
**[⬆ Back to Top](#table-of-contents)**
166. ### How do you detect a mobile browser
You can use regex which returns a true or false value depending on whether or not the user is browsing with a mobile.
```javascript
window.mobilecheck = function () {
var mobileCheck = false;
(function (a) {
if (
/(android|bb\d+|meego).+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|mobile.+firefox|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows ce|xda|xiino/i.test(
a
) ||
/1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas\-|your|zeto|zte\-/i.test(
a.substr(0, 4)
)
)
mobileCheck = true;
})(navigator.userAgent || navigator.vendor || window.opera);
return mobileCheck;
};
```
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167. ### How do you detect a mobile browser without regexp
You can detect mobile browsers by simply running through a list of devices and checking if the useragent matches anything. This is an alternative solution for RegExp usage,
```javascript
function detectmob() {
if (
navigator.userAgent.match(/Android/i) ||
navigator.userAgent.match(/webOS/i) ||
navigator.userAgent.match(/iPhone/i) ||
navigator.userAgent.match(/iPad/i) ||
navigator.userAgent.match(/iPod/i) ||
navigator.userAgent.match(/BlackBerry/i) ||
navigator.userAgent.match(/Windows Phone/i)
) {
return true;
} else {
return false;
}
}
```
**[⬆ Back to Top](#table-of-contents)**
168. ### How do you get the image width and height using JS
You can programmatically get the image and check the dimensions(width and height) using Javascript.
```javascript
var img = new Image();
img.onload = function () {
console.log(this.width + "x" + this.height);
};
img.src = "http://www.google.com/intl/en_ALL/images/logo.gif";
```
**[⬆ Back to Top](#table-of-contents)**
169. ### How do you make synchronous HTTP request
Browsers provide an XMLHttpRequest object which can be used to make synchronous HTTP requests from JavaScript
```javascript
function httpGet(theUrl) {
var xmlHttpReq = new XMLHttpRequest();
xmlHttpReq.open("GET", theUrl, false); // false for synchronous request
xmlHttpReq.send(null);
return xmlHttpReq.responseText;
}
```
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170. ### How do you make asynchronous HTTP request
Browsers provide an XMLHttpRequest object which can be used to make asynchronous HTTP requests from JavaScript by passing the 3rd parameter as true.
```javascript
function httpGetAsync(theUrl, callback) {
var xmlHttpReq = new XMLHttpRequest();
xmlHttpReq.onreadystatechange = function () {
if (xmlHttpReq.readyState == 4 && xmlHttpReq.status == 200)
callback(xmlHttpReq.responseText);
};
xmlHttp.open("GET", theUrl, true); // true for asynchronous
xmlHttp.send(null);
}
```
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171. ### How do you convert date to another timezone in javascript
You can use the toLocaleString() method to convert dates in one timezone to another. For example, let's convert current date to British English timezone as below,
```javascript
console.log(event.toLocaleString("en-GB", { timeZone: "UTC" })); //29/06/2019, 09:56:00
```
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172. ### What are the properties used to get size of window
You can use innerWidth, innerHeight, clientWidth, clientHeight properties of windows, document element and document body objects to find the size of a window. Let's use them combination of these properties to calculate the size of a window or document,
```javascript
var width =
window.innerWidth ||
document.documentElement.clientWidth ||
document.body.clientWidth;
var height =
window.innerHeight ||
document.documentElement.clientHeight ||
document.body.clientHeight;
```
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173. ### What is a conditional operator in javascript
The conditional (ternary) operator is the only JavaScript operator that takes three operands which acts as a shortcut for if statements.
```javascript
var isAuthenticated = false;
console.log(
isAuthenticated ? "Hello, welcome" : "Sorry, you are not authenticated"
); //Sorry, you are not authenticated
```
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174. ### Can you apply chaining on conditional operator
Yes, you can apply chaining on conditional operators similar to if … else if … else if … else chain. The syntax is going to be as below,
```javascript
function traceValue(someParam) {
return condition1
? value1
: condition2
? value2
: condition3
? value3
: value4;
}
// The above conditional operator is equivalent to:
function traceValue(someParam) {
if (condition1) {
return value1;
} else if (condition2) {
return value2;
} else if (condition3) {
return value3;
} else {
return value4;
}
}
```
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175. ### What are the ways to execute javascript after page load
You can execute javascript after page load in many different ways,
1. **window.onload:**
```javascript
window.onload = function ...
```
1. **document.onload:**
```javascript
document.onload = function ...
```
1. **body onload:**
```javascript
<body onload="script();">
```
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176. ### What is the difference between proto and prototype
The `__proto__` object is the actual object that is used in the lookup chain to resolve methods, etc. Whereas `prototype` is the object that is used to build `__proto__` when you create an object with new.
```javascript
new Employee().__proto__ === Employee.prototype;
new Employee().prototype === undefined;
```
There are few more differences,
| feature | Prototype | proto |
| ------------------- | ------------------------------------- | ----------------------------------------------- |
| Access | All the function constructors have prototype properties. | All the objects have \_\_proto__ property |
| Purpose | Used to reduce memory wastage with a single copy of function | Used in lookup chain to resolve methods, constructors etc. |
| ECMAScript | Introduced in ES6 | Introduced in ES5 |
| Usage | Frequently used | Rarely used |
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177. ### Give an example where do you really need semicolon
It is recommended to use semicolons after every statement in JavaScript. For example, in the below case it throws an error ".. is not a function" at runtime due to missing semicolon.
```javascript
// define a function
var fn = (function () {
//...
})(
// semicolon missing at this line
// then execute some code inside a closure
function () {
//...
}
)();
```
and it will be interpreted as
```javascript
var fn = (function () {
//...
})(function () {
//...
})();
```
In this case, we are passing the second function as an argument to the first function and then trying to call the result of the first function call as a function. Hence, the second function will fail with a "... is not a function" error at runtime.
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178. ### What is a freeze method
The **freeze()** method is used to freeze an object. Freezing an object does not allow adding new properties to an object,prevents from removing and prevents changing the enumerability, configurability, or writability of existing properties. i.e, It returns the passed object and does not create a frozen copy.
```javascript
const obj = {
prop: 100,
};
Object.freeze(obj);
obj.prop = 200; // Throws an error in strict mode
console.log(obj.prop); //100
```
Remember freezing is only applied to the top-level properties in objects but not for nested objects.
For example, let's try to freeze user object which has employment details as nested object and observe that details have been changed.
```javascript
const user = {
name: 'John',
employment: {
department: 'IT'
}
};
Object.freeze(user);
user.employment.department = 'HR';
```
**Note:** It causes a TypeError if the argument passed is not an object.
**[⬆ Back to Top](#table-of-contents)**
179. ### What is the purpose of freeze method
Below are the main benefits of using freeze method,
1. It is used for freezing objects and arrays.
2. It is used to make an object immutable.
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180. ### Why do I need to use freeze method
In the Object-oriented paradigm, an existing API contains certain elements that are not intended to be extended, modified, or re-used outside of their current context. Hence it works as the `final` keyword which is used in various languages.
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181. ### How do you detect a browser language preference
You can use navigator object to detect a browser language preference as below,
```javascript
var language =
(navigator.languages && navigator.languages[0]) || // Chrome / Firefox
navigator.language || // All browsers
navigator.userLanguage; // IE <= 10
console.log(language);
```
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182. ### How to convert string to title case with javascript
Title case means that the first letter of each word is capitalized. You can convert a string to title case using the below function,
```javascript
function toTitleCase(str) {
return str.replace(/\w\S*/g, function (txt) {
return txt.charAt(0).toUpperCase() + txt.substring(1).toLowerCase();
});
}
toTitleCase("good morning john"); // Good Morning John
```
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183. ### How do you detect javascript disabled in the page
You can use the `<noscript>` tag to detect javascript disabled or not. The code block inside `<noscript>` gets executed when JavaScript is disabled, and is typically used to display alternative content when the page generated in JavaScript.
```javascript
<script type="javascript">
// JS related code goes here
</script>
<noscript>
<a href="next_page.html?noJS=true">JavaScript is disabled in the page. Please click Next Page</a>
</noscript>
```
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184. ### What are various operators supported by javascript
An operator is capable of manipulating(mathematical and logical computations) a certain value or operand. There are various operators supported by JavaScript as below,
1. **Arithmetic Operators:** Includes + (Addition),– (Subtraction), \* (Multiplication), / (Division), % (Modulus), + + (Increment) and – – (Decrement)
2. **Comparison Operators:** Includes = =(Equal),!= (Not Equal), ===(Equal with type), > (Greater than),> = (Greater than or Equal to),< (Less than),<= (Less than or Equal to)
3. **Logical Operators:** Includes &&(Logical AND),||(Logical OR),!(Logical NOT)
4. **Assignment Operators:** Includes = (Assignment Operator), += (Add and Assignment Operator), – = (Subtract and Assignment Operator), \*= (Multiply and Assignment), /= (Divide and Assignment), %= (Modules and Assignment)
5. **Ternary Operators:** It includes conditional(: ?) Operator
6. **typeof Operator:** It uses to find type of variable. The syntax looks like `typeof variable`
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185. ### What is a rest parameter
Rest parameter is an improved way to handle function parameters which allows us to represent an indefinite number of arguments as an array. The syntax would be as below,
```javascript
function f(a, b, ...theArgs) {
// ...
}
```
For example, let's take a sum example to calculate on dynamic number of parameters,
```javascript
function total(…args){
let sum = 0;
for(let i of args){
sum+=i;
}
return sum;
}
console.log(fun(1,2)); //3
console.log(fun(1,2,3)); //6
console.log(fun(1,2,3,4)); //13
console.log(fun(1,2,3,4,5)); //15
```
**Note:** Rest parameter is added in ES2015 or ES6
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186. ### What happens if you do not use rest parameter as a last argument
The rest parameter should be the last argument, as its job is to collect all the remaining arguments into an array. For example, if you define a function like below it doesn’t make any sense and will throw an error.
```javascript
function someFunc(a,…b,c){
//You code goes here
return;
}
```
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187. ### What are the bitwise operators available in javascript
Below are the list of bitwise logical operators used in JavaScript
1. Bitwise AND ( & )
2. Bitwise OR ( | )
3. Bitwise XOR ( ^ )
4. Bitwise NOT ( ~ )
5. Left Shift ( << )
6. Sign Propagating Right Shift ( >> )
7. Zero fill Right Shift ( >>> )
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188. ### What is a spread operator
Spread operator allows iterables( arrays / objects / strings ) to be expanded into single arguments/elements. Let's take an example to see this behavior,
```javascript
function calculateSum(x, y, z) {
return x + y + z;
}
const numbers = [1, 2, 3];
console.log(calculateSum(...numbers)); // 6
```
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189. ### How do you determine whether object is frozen or not
Object.isFrozen() method is used to determine if an object is frozen or not.An object is frozen if all of the below conditions hold true,
1. If it is not extensible.
2. If all of its properties are non-configurable.
3. If all its data properties are non-writable.
The usage is going to be as follows,
```javascript
const object = {
property: "Welcome JS world",
};
Object.freeze(object);
console.log(Object.isFrozen(object));
```
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190. ### How do you determine two values same or not using object
The Object.is() method determines whether two values are the same value. For example, the usage with different types of values would be,
```javascript
Object.is("hello", "hello"); // true
Object.is(window, window); // true
Object.is([], []); // false
```
Two values are the same if one of the following holds:
1. both undefined
2. both null
3. both true or both false
4. both strings of the same length with the same characters in the same order
5. both the same object (means both object have same reference)
6. both numbers and
both +0
both -0
both NaN
both non-zero and both not NaN and both have the same value.
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191. ### What is the purpose of using object is method
Some of the applications of Object's `is` method are follows,
1. It is used for comparison of two strings.
2. It is used for comparison of two numbers.
3. It is used for comparing the polarity of two numbers.
4. It is used for comparison of two objects.
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192. ### How do you copy properties from one object to other
You can use the Object.assign() method which is used to copy the values and properties from one or more source objects to a target object. It returns the target object which has properties and values copied from the source objects. The syntax would be as below,
```javascript
Object.assign(target, ...sources);
```
Let's take example with one source and one target object,
```javascript
const target = { a: 1, b: 2 };
const source = { b: 3, c: 4 };
const returnedTarget = Object.assign(target, source);
console.log(target); // { a: 1, b: 3, c: 4 }
console.log(returnedTarget); // { a: 1, b: 3, c: 4 }
```
As observed in the above code, there is a common property(`b`) from source to target so it's value has been overwritten.
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193. ### What are the applications of assign method
Below are the some of main applications of Object.assign() method,
1. It is used for cloning an object.
2. It is used to merge objects with the same properties.
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194. ### What is a proxy object
The Proxy object is used to define custom behavior for fundamental operations such as property lookup, assignment, enumeration, function invocation, etc. The syntax would be as follows,
```javascript
var p = new Proxy(target, handler);
```
Let's take an example of proxy object,
```javascript
var handler = {
get: function (obj, prop) {
return prop in obj ? obj[prop] : 100;
},
};
var p = new Proxy({}, handler);
p.a = 10;
p.b = null;
console.log(p.a, p.b); // 10, null
console.log("c" in p, p.c); // false, 100
```
In the above code, it uses `get` handler which define the behavior of the proxy when an operation is performed on it
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195. ### What is the purpose of seal method
The **Object.seal()** method is used to seal an object, by preventing new properties from being added to it and marking all existing properties as non-configurable. But values of present properties can still be changed as long as they are writable. Let's see the below example to understand more about seal() method
```javascript
const object = {
property: "Welcome JS world",
};
Object.seal(object);
object.property = "Welcome to object world";
console.log(Object.isSealed(object)); // true
delete object.property; // You cannot delete when sealed
console.log(object.property); //Welcome to object world
```
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196. ### What are the applications of seal method
Below are the main applications of Object.seal() method,
1. It is used for sealing objects and arrays.
2. It is used to make an object immutable.
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197. ### What are the differences between freeze and seal methods
If an object is frozen using the Object.freeze() method then its properties become immutable and no changes can be made in them whereas if an object is sealed using the Object.seal() method then the changes can be made in the existing properties of the object.
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198. ### How do you determine if an object is sealed or not
The Object.isSealed() method is used to determine if an object is sealed or not. An object is sealed if all of the below conditions hold true
1. If it is not extensible.
2. If all of its properties are non-configurable.
3. If it is not removable (but not necessarily non-writable).
Let's see it in the action
```javascript
const object = {
property: "Hello, Good morning",
};
Object.seal(object); // Using seal() method to seal the object
console.log(Object.isSealed(object)); // checking whether the object is sealed or not
```
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199. ### How do you get enumerable key and value pairs
The Object.entries() method is used to return an array of a given object's own enumerable string-keyed property [key, value] pairs, in the same order as that provided by a for...in loop. Let's see the functionality of object.entries() method in an example,
```javascript
const object = {
a: "Good morning",
b: 100,
};
for (let [key, value] of Object.entries(object)) {
console.log(`${key}: ${value}`); // a: 'Good morning'
// b: 100
}
```
**Note:** The order is not guaranteed as object defined.
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200. ### What is the main difference between Object.values and Object.entries method
The Object.values() method's behavior is similar to Object.entries() method but it returns an array of values instead [key,value] pairs.
```javascript
const object = {
a: "Good morning",
b: 100,
};
for (let value of Object.values(object)) {
console.log(`${value}`); // 'Good morning'
100;
}
```
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201. ### How can you get the list of keys of any object
You can use the `Object.keys()` method which is used to return an array of a given object's own property names, in the same order as we get with a normal loop. For example, you can get the keys of a user object,
```javascript
const user = {
name: "John",
gender: "male",
age: 40,
};
console.log(Object.keys(user)); //['name', 'gender', 'age']
```
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202. ### How do you create an object with prototype
The Object.create() method is used to create a new object with the specified prototype object and properties. i.e, It uses an existing object as the prototype of the newly created object. It returns a new object with the specified prototype object and properties.
```javascript
const user = {
name: "John",
printInfo: function () {
console.log(`My name is ${this.name}.`);
},
};
const admin = Object.create(user);
admin.name = "Nick"; // Remember that "name" is a property set on "admin" but not on "user" object
admin.printInfo(); // My name is Nick
```
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203. ### What is a WeakSet
WeakSet is used to store a collection of weakly(weak references) held objects. The syntax would be as follows,
```javascript
new WeakSet([iterable]);
```
Let's see the below example to explain it's behavior,
```javascript
var ws = new WeakSet();
var user = {};
ws.add(user);
ws.has(user); // true
ws.delete(user); // removes user from the set
ws.has(user); // false, user has been removed
```
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204. ### What are the differences between WeakSet and Set
The main difference is that references to objects in Set are strong while references to objects in WeakSet are weak. i.e, An object in WeakSet can be garbage collected if there is no other reference to it.
Other differences are,
1. Sets can store any value Whereas WeakSets can store only collections of objects
2. WeakSet does not have size property unlike Set
3. WeakSet does not have methods such as clear, keys, values, entries, forEach.
4. WeakSet is not iterable.
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205. ### List down the collection of methods available on WeakSet
Below are the list of methods available on WeakSet,
1. add(value): A new object is appended with the given value to the weakset
2. delete(value): Deletes the value from the WeakSet collection.
3. has(value): It returns true if the value is present in the WeakSet Collection, otherwise it returns false.
Let's see the functionality of all the above methods in an example,
```javascript
var weakSetObject = new WeakSet();
var firstObject = {};
var secondObject = {};
// add(value)
weakSetObject.add(firstObject);
weakSetObject.add(secondObject);
console.log(weakSetObject.has(firstObject)); //true
weakSetObject.delete(secondObject);
```
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206. ### What is a WeakMap
The WeakMap object is a collection of key/value pairs in which the keys are weakly referenced. In this case, keys must be objects and the values can be arbitrary values. The syntax is looking like as below,
```javascript
new WeakMap([iterable]);
```
Let's see the below example to explain it's behavior,
```javascript
var ws = new WeakMap();
var user = {};
ws.set(user);
ws.has(user); // true
ws.delete(user); // removes user from the map
ws.has(user); // false, user has been removed
```
**[⬆ Back to Top](#table-of-contents)**
207. ### What are the differences between WeakMap and Map
The main difference is that references to key objects in Map are strong while references to key objects in WeakMap are weak. i.e, A key object in WeakMap can be garbage collected if there is no other reference to it.
Other differences are,
1. Maps can store any key type Whereas WeakMaps can store only collections of key objects
2. WeakMap does not have size property unlike Map
3. WeakMap does not have methods such as clear, keys, values, entries, forEach.
4. WeakMap is not iterable.
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208. ### List down the collection of methods available on WeakMap
Below are the list of methods available on WeakMap,
1. set(key, value): Sets the value for the key in the WeakMap object. Returns the WeakMap object.
2. delete(key): Removes any value associated to the key.
3. has(key): Returns a Boolean asserting whether a value has been associated to the key in the WeakMap object or not.
4. get(key): Returns the value associated to the key, or undefined if there is none.
Let's see the functionality of all the above methods in an example,
```javascript
var weakMapObject = new WeakMap();
var firstObject = {};
var secondObject = {};
// set(key, value)
weakMapObject.set(firstObject, "John");
weakMapObject.set(secondObject, 100);
console.log(weakMapObject.has(firstObject)); //true
console.log(weakMapObject.get(firstObject)); // John
weakMapObject.delete(secondObject);
```
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209. ### What is the purpose of uneval
The uneval() is an inbuilt function which is used to create a string representation of the source code of an Object. It is a top-level function and is not associated with any object. Let's see the below example to know more about it's functionality,
```javascript
var a = 1;
uneval(a); // returns a String containing 1
uneval(function user() {}); // returns "(function user(){})"
```
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210. ### How do you encode an URL
The encodeURI() function is used to encode complete URI which has special characters except (, / ? : @ & = + $ #) characters.
```javascript
var uri = "https://mozilla.org/?x=шеллы";
var encoded = encodeURI(uri);
console.log(encoded); // https://mozilla.org/?x=%D1%88%D0%B5%D0%BB%D0%BB%D1%8B
```
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211. ### How do you decode an URL
The decodeURI() function is used to decode a Uniform Resource Identifier (URI) previously created by encodeURI().
```javascript
var uri = "https://mozilla.org/?x=шеллы";
var encoded = encodeURI(uri);
console.log(encoded); // https://mozilla.org/?x=%D1%88%D0%B5%D0%BB%D0%BB%D1%8B
try {
console.log(decodeURI(encoded)); // "https://mozilla.org/?x=шеллы"
} catch (e) {
// catches a malformed URI
console.error(e);
}
```
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212. ### How do you print the contents of web page
The window object provided a print() method which is used to print the contents of the current window. It opens a Print dialog box which lets you choose between various printing options. Let's see the usage of print method in an example,
```html
<input type="button" value="Print" onclick="window.print()" />
```
**Note:** In most browsers, it will block while the print dialog is open.
**[⬆ Back to Top](#table-of-contents)**
213. ### What is the difference between uneval and eval
The `uneval` function returns the source of a given object; whereas the `eval` function does the opposite, by evaluating that source code in a different memory area. Let's see an example to clarify the difference,
```javascript
var msg = uneval(function greeting() {
return "Hello, Good morning";
});
var greeting = eval(msg);
greeting(); // returns "Hello, Good morning"
```
**[⬆ Back to Top](#table-of-contents)**
214. ### What is an anonymous function
An anonymous function is a function without a name! Anonymous functions are commonly assigned to a variable name or used as a callback function. The syntax would be as below,
```javascript
function (optionalParameters) {
//do something
}
const myFunction = function(){ //Anonymous function assigned to a variable
//do something
};
[1, 2, 3].map(function(element){ //Anonymous function used as a callback function
//do something
});
```
Let's see the above anonymous function in an example,
```javascript
var x = function (a, b) {
return a * b;
};
var z = x(5, 10);
console.log(z); // 50
```
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215. ### What is the precedence order between local and global variables
A local variable takes precedence over a global variable with the same name. Let's see this behavior in an example.
```javascript
var msg = "Good morning";
function greeting() {
msg = "Good Evening";
console.log(msg); // Good Evening
}
greeting();
```
**[⬆ Back to Top](#table-of-contents)**
216. ### What are javascript accessors
ECMAScript 5 introduced javascript object accessors or computed properties through getters and setters. Getters uses the `get` keyword whereas Setters uses the `set` keyword.
```javascript
var user = {
firstName: "John",
lastName : "Abraham",
language : "en",
get lang() {
return this.language;
},
set lang(lang) {
this.language = lang;
}
};
console.log(user.lang); // getter access lang as en
user.lang = 'fr';
console.log(user.lang); // setter used to set lang as fr
```
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217. ### How do you define property on Object constructor
The Object.defineProperty() static method is used to define a new property directly on an object, or modify an existing property on an object, and returns the object. Let's see an example to know how to define property,
```javascript
const newObject = {};
Object.defineProperty(newObject, "newProperty", {
value: 100,
writable: false,
});
console.log(newObject.newProperty); // 100
newObject.newProperty = 200; // It throws an error in strict mode due to writable setting
```
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218. ### What is the difference between get and defineProperty
Both have similar results until unless you use classes. If you use `get` the property will be defined on the prototype of the object whereas using `Object.defineProperty()` the property will be defined on the instance it is applied to.
**[⬆ Back to Top](#table-of-contents)**
219. ### What are the advantages of Getters and Setters
Below are the list of benefits of Getters and Setters,
1. They provide simpler syntax
2. They are used for defining computed properties, or accessors in JS.
3. Useful to provide equivalence relation between properties and methods
4. They can provide better data quality
5. Useful for doing things behind the scenes with the encapsulated logic.
**[⬆ Back to Top](#table-of-contents)**
220. ### Can I add getters and setters using defineProperty method
Yes, You can use the `Object.defineProperty()` method to add Getters and Setters. For example, the below counter object uses increment, decrement, add and subtract properties,
```javascript
var obj = { counter: 0 };
// Define getters
Object.defineProperty(obj, "increment", {
get: function () {
this.counter++;
},
});
Object.defineProperty(obj, "decrement", {
get: function () {
this.counter--;
},
});
// Define setters
Object.defineProperty(obj, "add", {
set: function (value) {
this.counter += value;
},
});
Object.defineProperty(obj, "subtract", {
set: function (value) {
this.counter -= value;
},
});
obj.add = 10;
obj.subtract = 5;
console.log(obj.increment); //6
console.log(obj.decrement); //5
```
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221. ### What is the purpose of switch-case
The switch case statement in JavaScript is used for decision making purposes. In a few cases, using the switch case statement is going to be more convenient than if-else statements. The syntax would be as below,
```javascript
switch (expression)
{
case value1:
statement1;
break;
case value2:
statement2;
break;
.
.
case valueN:
statementN;
break;
default:
statementDefault;
}
```
The above multi-way branch statement provides an easy way to dispatch execution to different parts of code based on the value of the expression.
**[⬆ Back to Top](#table-of-contents)**
222. ### What are the conventions to be followed for the usage of switch case
Below are the list of conventions should be taken care,
1. The expression can be of type either number or string.
2. Duplicate values are not allowed for the expression.
3. The default statement is optional. If the expression passed to switch does not match with any case value then the statement within default case will be executed.
4. The break statement is used inside the switch to terminate a statement sequence.
5. The break statement is optional. But if it is omitted, the execution will continue on into the next case.
**[⬆ Back to Top](#table-of-contents)**
223. ### What are primitive data types
A primitive data type is data that has a primitive value (which has no properties or methods). There are 7 types of primitive data types.
1. string
2. number
3. boolean
4. null
5. undefined
6. bigint
7. symbol
**[⬆ Back to Top](#table-of-contents)**
224. ### What are the different ways to access object properties
There are 3 possible ways for accessing the property of an object.
1. **Dot notation:** It uses dot for accessing the properties
```javascript
objectName.property;
```
1. **Square brackets notation:** It uses square brackets for property access
```javascript
objectName["property"];
```
1. **Expression notation:** It uses expression in the square brackets
```javascript
objectName[expression];
```
**[⬆ Back to Top](#table-of-contents)**
225. ### What are the function parameter rules
JavaScript functions follow below rules for parameters,
1. The function definitions do not specify data types for parameters.
2. Do not perform type checking on the passed arguments.
3. Do not check the number of arguments received.
i.e, The below function follows the above rules,
```javascript
function functionName(parameter1, parameter2, parameter3) {
console.log(parameter1); // 1
}
functionName(1);
```
**[⬆ Back to Top](#table-of-contents)**
226. ### What is an error object
An error object is a built in error object that provides error information when an error occurs. It has two properties: name and message. For example, the below function logs error details,
```javascript
try {
greeting("Welcome");
} catch (err) {
console.log(err.name + "<br>" + err.message);
}
```
**[⬆ Back to Top](#table-of-contents)**
227. ### When you get a syntax error
A SyntaxError is thrown if you try to evaluate code with a syntax error. For example, the below missing quote for the function parameter throws a syntax error
```javascript
try {
eval("greeting('welcome)"); // Missing ' will produce an error
} catch (err) {
console.log(err.name);
}
```
**[⬆ Back to Top](#table-of-contents)**
228. ### What are the different error names from error object
There are 6 different types of error names returned from error object,
| Error Name | Description |
|---- | ---------
| EvalError | An error has occurred in the eval() function |
| RangeError | An error has occurred with a number "out of range" |
| ReferenceError | An error due to an illegal reference|
| SyntaxError | An error due to a syntax error|
| TypeError | An error due to a type error |
| URIError | An error due to encodeURI() |
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229. ### What are the various statements in error handling
Below are the list of statements used in an error handling,
1. **try:** This statement is used to test a block of code for errors
2. **catch:** This statement is used to handle the error
3. **throw:** This statement is used to create custom errors.
4. **finally:** This statement is used to execute code after try and catch regardless of the result.
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230. ### What are the two types of loops in javascript
1. **Entry Controlled loops:** In this kind of loop type, the test condition is tested before entering the loop body. For example, For Loop and While Loop comes under this category.
2. **Exit Controlled Loops:** In this kind of loop type, the test condition is tested or evaluated at the end of the loop body. i.e, the loop body will execute at least once irrespective of test condition true or false. For example, do-while loop comes under this category.
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231. ### What is nodejs
Node.js is a server-side platform built on Chrome's JavaScript runtime for easily building fast and scalable network applications. It is an event-based, non-blocking, asynchronous I/O runtime that uses Google's V8 JavaScript engine and libuv library.
**[⬆ Back to Top](#table-of-contents)**
232. ### What is an Intl object
The Intl object is the namespace for the ECMAScript Internationalization API, which provides language sensitive string comparison, number formatting, and date and time formatting. It provides access to several constructors and language sensitive functions.
**[⬆ Back to Top](#table-of-contents)**
233. ### How do you perform language specific date and time formatting
You can use the `Intl.DateTimeFormat` object which is a constructor for objects that enable language-sensitive date and time formatting. Let's see this behavior with an example,
```javascript
var date = new Date(Date.UTC(2019, 07, 07, 3, 0, 0));
console.log(new Intl.DateTimeFormat("en-GB").format(date)); // 07/08/2019
console.log(new Intl.DateTimeFormat("en-AU").format(date)); // 07/08/2019
```
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234. ### What is an Iterator
An iterator is an object which defines a sequence and a return value upon its termination. It implements the Iterator protocol with a `next()` method which returns an object with two properties: `value` (the next value in the sequence) and `done` (which is true if the last value in the sequence has been consumed).
**[⬆ Back to Top](#table-of-contents)**
235. ### How does synchronous iteration works
Synchronous iteration was introduced in ES6 and it works with below set of components,
**Iterable:** It is an object which can be iterated over via a method whose key is Symbol.iterator.
**Iterator:** It is an object returned by invoking `[Symbol.iterator]()` on an iterable. This iterator object wraps each iterated element in an object and returns it via `next()` method one by one.
**IteratorResult:** It is an object returned by `next()` method. The object contains two properties; the `value` property contains an iterated element and the `done` property determines whether the element is the last element or not.
Let's demonstrate synchronous iteration with an array as below,
```javascript
const iterable = ["one", "two", "three"];
const iterator = iterable[Symbol.iterator]();
console.log(iterator.next()); // { value: 'one', done: false }
console.log(iterator.next()); // { value: 'two', done: false }
console.log(iterator.next()); // { value: 'three', done: false }
console.log(iterator.next()); // { value: 'undefined, done: true }
```
**[⬆ Back to Top](#table-of-contents)**
236. ### What is an event loop
The event loop is a process that continuously monitors both the call stack and the event queue and checks whether or not the call stack is empty. If the call stack is empty and there are pending events in the event queue, the event loop dequeues the event from the event queue and pushes it to the call stack. The call stack executes the event, and any additional events generated during the execution are added to the end of the event queue.
**Note:** The event loop allows Node.js to perform non-blocking I/O operations, even though JavaScript is single-threaded, by offloading operations to the system kernel whenever possible. Since most modern kernels are multi-threaded, they can handle multiple operations executing in the background.
**[⬆ Back to Top](#table-of-contents)**
237. ### What is call stack
Call Stack is a data structure for javascript interpreters to keep track of function calls(creates execution context) in the program. It has two major actions,
1. Whenever you call a function for its execution, you are pushing it to the stack.
2. Whenever the execution is completed, the function is popped out of the stack.
Let's take an example and it's state representation in a diagram format
```javascript
function hungry() {
eatFruits();
}
function eatFruits() {
return "I'm eating fruits";
}
// Invoke the `hungry` function
hungry();
```
The above code processed in a call stack as below,
1. Add the `hungry()` function to the call stack list and execute the code.
2. Add the `eatFruits()` function to the call stack list and execute the code.
3. Delete the `eatFruits()` function from our call stack list.
4. Delete the `hungry()` function from the call stack list since there are no items anymore.
**[⬆ Back to Top](#table-of-contents)**
238. ### What is an event queue
The event queue follows the queue data structure. It stores async callbacks to be added to the call stack. It is also known as the Callback Queue or Macrotask Queue.
Whenever the call stack receives an async function, it is moved into the Web API. Based on the function, Web API executes it and awaits the result. Once it is finished, it moves the callback into the event queue (the callback of the promise is moved into the microtask queue).
The event queue constantly checks whether or not the call stack is empty. Once the call stack is empty and there is a callback in the event queue, the event queue moves the callback into the call stack. If there is a callback in the microtask queue as well, it is moved first. The microtask queue has a higher priority than the event queue.
**[⬆ Back to Top](#table-of-contents)**
239. ### What is a decorator
A decorator is an expression that evaluates to a function and that takes the target, name, and decorator descriptor as arguments. Also, it optionally returns a decorator descriptor to install on the target object. Let's define admin decorator for user class at design time,
```javascript
function admin(isAdmin) {
return function(target) {
target.isAdmin = isAdmin;
}
}
@admin(true)
class User() {
}
console.log(User.isAdmin); //true
@admin(false)
class User() {
}
console.log(User.isAdmin); //false
```
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240. ### What are the properties of Intl object
Below are the list of properties available on Intl object,
1. **Collator:** These are the objects that enable language-sensitive string comparison.
2. **DateTimeFormat:** These are the objects that enable language-sensitive date and time formatting.
3. **ListFormat:** These are the objects that enable language-sensitive list formatting.
4. **NumberFormat:** Objects that enable language-sensitive number formatting.
5. **PluralRules:** Objects that enable plural-sensitive formatting and language-specific rules for plurals.
6. **RelativeTimeFormat:** Objects that enable language-sensitive relative time formatting.
**[⬆ Back to Top](#table-of-contents)**
241. ### What is an Unary operator
The unary(+) operator is used to convert a variable to a number.If the variable cannot be converted, it will still become a number but with the value NaN. Let's see this behavior in an action.
```javascript
var x = "100";
var y = +x;
console.log(typeof x, typeof y); // string, number
var a = "Hello";
var b = +a;
console.log(typeof a, typeof b, b); // string, number, NaN
```
**[⬆ Back to Top](#table-of-contents)**
242. ### How do you sort elements in an array
The sort() method is used to sort the elements of an array in place and returns the sorted array. The example usage would be as below,
```javascript
var months = ["Aug", "Sep", "Jan", "June"];
months.sort();
console.log(months); // ["Aug", "Jan", "June", "Sep"]
```
**[⬆ Back to Top](#table-of-contents)**
243. ### What is the purpose of compareFunction while sorting arrays
The compareFunction is used to define the sort order. If omitted, the array elements are converted to strings, then sorted according to each character's Unicode code point value. Let's take an example to see the usage of compareFunction,
```javascript
let numbers = [1, 2, 5, 3, 4];
numbers.sort((a, b) => b - a);
console.log(numbers); // [5, 4, 3, 2, 1]
```
**[⬆ Back to Top](#table-of-contents)**
244. ### How do you reversing an array
You can use the reverse() method to reverse the elements in an array. This method is useful to sort an array in descending order. Let's see the usage of reverse() method in an example,
```javascript
let numbers = [1, 2, 5, 3, 4];
numbers.sort((a, b) => b - a);
numbers.reverse();
console.log(numbers); // [1, 2, 3, 4 ,5]
```
**[⬆ Back to Top](#table-of-contents)**
245. ### How do you find min and max value in an array
You can use `Math.min` and `Math.max` methods on array variables to find the minimum and maximum elements within an array. Let's create two functions to find the min and max value with in an array,
```javascript
var marks = [50, 20, 70, 60, 45, 30];
function findMin(arr) {
return Math.min.apply(null, arr);
}
function findMax(arr) {
return Math.max.apply(null, arr);
}
console.log(findMin(marks));
console.log(findMax(marks));
```
**[⬆ Back to Top](#table-of-contents)**
246. ### How do you find min and max values without Math functions
You can write functions which loop through an array comparing each value with the lowest value or highest value to find the min and max values. Let's create those functions to find min and max values,
```javascript
var marks = [50, 20, 70, 60, 45, 30];
function findMin(arr) {
var length = arr.length;
var min = Infinity;
while (length--) {
if (arr[length] < min) {
min = arr[length];
}
}
return min;
}
function findMax(arr) {
var length = arr.length;
var max = -Infinity;
while (length--) {
if (arr[length] > max) {
max = arr[length];
}
}
return max;
}
console.log(findMin(marks));
console.log(findMax(marks));
```
**[⬆ Back to Top](#table-of-contents)**
247. ### What is an empty statement and purpose of it
The empty statement is a semicolon (;) indicating that no statement will be executed, even if JavaScript syntax requires one. Since there is no action with an empty statement you might think that it's usage is quite less, but the empty statement is occasionally useful when you want to create a loop that has an empty body. For example, you can initialize an array with zero values as below,
```javascript
// Initialize an array a
for(let i=0; i < a.length; a[i++] = 0) ;
```
**[⬆ Back to Top](#table-of-contents)**
248. ### How do you get metadata of a module
You can use the `import.meta` object which is a meta-property exposing context-specific meta data to a JavaScript module. It contains information about the current module, such as the module's URL. In browsers, you might get different meta data than NodeJS.
```javascript
<script type="module" src="welcome-module.js"></script>;
console.log(import.meta); // { url: "file:///home/user/welcome-module.js" }
```
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249. ### What is a comma operator
The comma operator is used to evaluate each of its operands from left to right and returns the value of the last operand. This is totally different from comma usage within arrays, objects, and function arguments and parameters. For example, the usage for numeric expressions would be as below,
```javascript
var x = 1;
x = (x++, x);
console.log(x); // 2
```
**[⬆ Back to Top](#table-of-contents)**
250. ### What is the advantage of a comma operator
It is normally used to include multiple expressions in a location that requires a single expression. One of the common usages of this comma operator is to supply multiple parameters in a `for` loop. For example, the below for loop uses multiple expressions in a single location using comma operator,
```javascript
for (var a = 0, b =10; a <= 10; a++, b--)
```
You can also use the comma operator in a return statement where it processes before returning.
```javascript
function myFunction() {
var a = 1;
return (a += 10), a; // 11
}
```
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251. ### What is typescript
TypeScript is a typed superset of JavaScript created by Microsoft that adds optional types, classes, async/await, and many other features, and compiles to plain JavaScript. Angular built entirely in TypeScript and used as a primary language. You can install it globally as
```bash
npm install -g typescript
```
Let's see a simple example of TypeScript usage,
```typescript
function greeting(name: string): string {
return "Hello, " + name;
}
let user = "Sudheer";
console.log(greeting(user));
```
The greeting method allows only string type as argument.
**[⬆ Back to Top](#table-of-contents)**
252. ### What are the differences between javascript and typescript
Below are the list of differences between javascript and typescript,
| feature | typescript | javascript |
| ------------------- | ------------------------------------- | ----------------------------------------------- |
| Language paradigm | Object oriented programming language | Scripting language |
| Typing support | Supports static typing | It has dynamic typing |
| Modules | Supported | Not supported |
| Interface | It has interfaces concept | Doesn't support interfaces |
| Optional parameters | Functions support optional parameters | No support of optional parameters for functions |
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253. ### What are the advantages of typescript over javascript
Below are some of the advantages of typescript over javascript,
1. TypeScript is able to find compile time errors at the development time only and it makes sures less runtime errors. Whereas javascript is an interpreted language.
2. TypeScript is strongly-typed or supports static typing which allows for checking type correctness at compile time. This is not available in javascript.
3. TypeScript compiler can compile the .ts files into ES3,ES4 and ES5 unlike ES6 features of javascript which may not be supported in some browsers.
**[⬆ Back to Top](#table-of-contents)**
254. ### What is an object initializer
An object initializer is an expression that describes the initialization of an Object. The syntax for this expression is represented as a comma-delimited list of zero or more pairs of property names and associated values of an object, enclosed in curly braces ({}). This is also known as literal notation. It is one of the ways to create an object.
```javascript
var initObject = { a: "John", b: 50, c: {} };
console.log(initObject.a); // John
```
**[⬆ Back to Top](#table-of-contents)**
255. ### What is a constructor method
The constructor method is a special method for creating and initializing an object created within a class. If you do not specify a constructor method, a default constructor is used. The example usage of constructor would be as below,
```javascript
class Employee {
constructor() {
this.name = "John";
}
}
var employeeObject = new Employee();
console.log(employeeObject.name); // John
```
**[⬆ Back to Top](#table-of-contents)**
256. ### What happens if you write constructor more than once in a class
The "constructor" in a class is a special method and it should be defined only once in a class. i.e, If you write a constructor method more than once in a class it will throw a `SyntaxError` error.
```javascript
class Employee {
constructor() {
this.name = "John";
}
constructor() { // Uncaught SyntaxError: A class may only have one constructor
this.age = 30;
}
}
var employeeObject = new Employee();
console.log(employeeObject.name);
```
**[⬆ Back to Top](#table-of-contents)**
257. ### How do you call the constructor of a parent class
You can use the `super` keyword to call the constructor of a parent class. Remember that `super()` must be called before using 'this' reference. Otherwise it will cause a reference error. Let's the usage of it,
```javascript
class Square extends Rectangle {
constructor(length) {
super(length, length);
this.name = "Square";
}
get area() {
return this.width * this.height;
}
set area(value) {
this.area = value;
}
}
```
**[⬆ Back to Top](#table-of-contents)**
258. ### How do you get the prototype of an object
You can use the `Object.getPrototypeOf(obj)` method to return the prototype of the specified object. i.e. The value of the internal `prototype` property. If there are no inherited properties then `null` value is returned.
```javascript
const newPrototype = {};
const newObject = Object.create(newPrototype);
console.log(Object.getPrototypeOf(newObject) === newPrototype); // true
```
**[⬆ Back to Top](#table-of-contents)**
259. ### What happens If I pass string type for getPrototype method
In ES5, it will throw a TypeError exception if the obj parameter isn't an object. Whereas in ES2015, the parameter will be coerced to an `Object`.
```javascript
// ES5
Object.getPrototypeOf("James"); // TypeError: "James" is not an object
// ES2015
Object.getPrototypeOf("James"); // String.prototype
```
**[⬆ Back to Top](#table-of-contents)**
260. ### How do you set prototype of one object to another
You can use the `Object.setPrototypeOf()` method that sets the prototype (i.e., the internal `Prototype` property) of a specified object to another object or null. For example, if you want to set prototype of a square object to rectangle object would be as follows,
```javascript
Object.setPrototypeOf(Square.prototype, Rectangle.prototype);
Object.setPrototypeOf({}, null);
```
**[⬆ Back to Top](#table-of-contents)**
261. ### How do you check whether an object can be extendable or not
The `Object.isExtensible()` method is used to determine if an object is extendable or not. i.e, Whether it can have new properties added to it or not.
```javascript
const newObject = {};
console.log(Object.isExtensible(newObject)); //true
```
**Note:** By default, all the objects are extendable. i.e, The new properties can be added or modified.
**[⬆ Back to Top](#table-of-contents)**
262. ### How do you prevent an object to extend
The `Object.preventExtensions()` method is used to prevent new properties from ever being added to an object. In other words, it prevents future extensions to the object. Let's see the usage of this property,
```javascript
const newObject = {};
Object.preventExtensions(newObject); // NOT extendable
try {
Object.defineProperty(newObject, "newProperty", {
// Adding new property
value: 100,
});
} catch (e) {
console.log(e); // TypeError: Cannot define property newProperty, object is not extensible
}
```
**[⬆ Back to Top](#table-of-contents)**
263. ### What are the different ways to make an object non-extensible
You can mark an object non-extensible in 3 ways,
1. Object.preventExtensions
2. Object.seal
3. Object.freeze
```javascript
var newObject = {};
Object.preventExtensions(newObject); // Prevent objects are non-extensible
Object.isExtensible(newObject); // false
var sealedObject = Object.seal({}); // Sealed objects are non-extensible
Object.isExtensible(sealedObject); // false
var frozenObject = Object.freeze({}); // Frozen objects are non-extensible
Object.isExtensible(frozenObject); // false
```
**[⬆ Back to Top](#table-of-contents)**
264. ### How do you define multiple properties on an object
The `Object.defineProperties()` method is used to define new or modify existing properties directly on an object and returning the object. Let's define multiple properties on an empty object,
```javascript
const newObject = {};
Object.defineProperties(newObject, {
newProperty1: {
value: "John",
writable: true,
},
newProperty2: {},
});
```
**[⬆ Back to Top](#table-of-contents)**
265. ### What is MEAN in javascript
The MEAN (MongoDB, Express, AngularJS, and Node.js) stack is the most popular open-source JavaScript software tech stack available for building dynamic web apps where you can write both the server-side and client-side halves of the web project entirely in JavaScript.
**[⬆ Back to Top](#table-of-contents)**
266. ### What Is Obfuscation in javascript
Obfuscation is the deliberate act of creating obfuscated javascript code(i.e, source or machine code) that is difficult for humans to understand. It is something similar to encryption, but a machine can understand the code and execute it.
Let's see the below function before Obfuscation,
```javascript
function greeting() {
console.log("Hello, welcome to JS world");
}
```
And after the code Obfuscation, it would be appeared as below,
```javascript
eval(
(function (p, a, c, k, e, d) {
e = function (c) {
return c;
};
if (!"".replace(/^/, String)) {
while (c--) {
d[c] = k[c] || c;
}
k = [
function (e) {
return d[e];
},
];
e = function () {
return "\\w+";
};
c = 1;
}
while (c--) {
if (k[c]) {
p = p.replace(new RegExp("\\b" + e(c) + "\\b", "g"), k[c]);
}
}
return p;
})(
"2 1(){0.3('4, 7 6 5 8')}",
9,
9,
"console|greeting|function|log|Hello|JS|to|welcome|world".split("|"),
0,
{}
)
);
```
**[⬆ Back to Top](#table-of-contents)**
267. ### Why do you need Obfuscation
Below are the few reasons for Obfuscation,
1. The Code size will be reduced. So data transfers between server and client will be fast.
2. It hides the business logic from outside world and protects the code from others
3. Reverse engineering is highly difficult
4. The download time will be reduced
**[⬆ Back to Top](#table-of-contents)**
268. ### What is Minification
Minification is the process of removing all unnecessary characters(empty spaces are removed) and variables will be renamed without changing it's functionality. It is also a type of obfuscation .
**[⬆ Back to Top](#table-of-contents)**
269. ### What are the advantages of minification
Normally it is recommended to use minification for heavy traffic and intensive requirements of resources. It reduces file sizes with below benefits,
1. Decreases loading times of a web page
2. Saves bandwidth usages
**[⬆ Back to Top](#table-of-contents)**
270. ### What are the differences between Obfuscation and Encryption
Below are the main differences between Obfuscation and Encryption,
| Feature | Obfuscation | Encryption |
| ------------------ | ----------------------------------------------- | ----------------------------------------------------------------------- |
| Definition | Changing the form of any data in any other form | Changing the form of information to an unreadable format by using a key |
| A key to decode | It can be decoded without any key | It is required |
| Target data format | It will be converted to a complex form | Converted into an unreadable format |
**[⬆ Back to Top](#table-of-contents)**
271. ### What are the common tools used for minification
There are many online/offline tools to minify the javascript files,
1. Google's Closure Compiler
2. UglifyJS2
3. jsmin
4. javascript-minifier.com/
5. prettydiff.com
**[⬆ Back to Top](#table-of-contents)**
272. ### How do you perform form validation using javascript
JavaScript can be used to perform HTML form validation. For example, if the form field is empty, the function needs to notify, and return false, to prevent the form being submitted.
Lets' perform user login in an html form,
```html
<form name="myForm" onsubmit="return validateForm()" method="post">
User name: <input type="text" name="uname" />
<input type="submit" value="Submit" />
</form>
```
And the validation on user login is below,
```javascript
function validateForm() {
var x = document.forms["myForm"]["uname"].value;
if (x == "") {
alert("The username shouldn't be empty");
return false;
}
}
```
**[⬆ Back to Top](#table-of-contents)**
273. ### How do you perform form validation without javascript
You can perform HTML form validation automatically without using javascript. The validation enabled by applying the `required` attribute to prevent form submission when the input is empty.
```html
<form method="post">
<input type="text" name="uname" required />
<input type="submit" value="Submit" />
</form>
```
**Note:** Automatic form validation does not work in Internet Explorer 9 or earlier.
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274. ### What are the DOM methods available for constraint validation
The below DOM methods are available for constraint validation on an invalid input,
1. checkValidity(): It returns true if an input element contains valid data.
2. setCustomValidity(): It is used to set the validationMessage property of an input element.
Let's take an user login form with DOM validations
```javascript
function myFunction() {
var userName = document.getElementById("uname");
if (!userName.checkValidity()) {
document.getElementById("message").innerHTML =
userName.validationMessage;
} else {
document.getElementById("message").innerHTML =
"Entered a valid username";
}
}
```
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275. ### What are the available constraint validation DOM properties
Below are the list of some of the constraint validation DOM properties available,
1. validity: It provides a list of boolean properties related to the validity of an input element.
2. validationMessage: It displays the message when the validity is false.
3. willValidate: It indicates if an input element will be validated or not.
**[⬆ Back to Top](#table-of-contents)**
276. ### What are the list of validity properties
The validity property of an input element provides a set of properties related to the validity of data.
1. customError: It returns true, if a custom validity message is set.
2. patternMismatch: It returns true, if an element's value does not match its pattern attribute.
3. rangeOverflow: It returns true, if an element's value is greater than its max attribute.
4. rangeUnderflow: It returns true, if an element's value is less than its min attribute.
5. stepMismatch: It returns true, if an element's value is invalid according to step attribute.
6. tooLong: It returns true, if an element's value exceeds its maxLength attribute.
7. typeMismatch: It returns true, if an element's value is invalid according to type attribute.
8. valueMissing: It returns true, if an element with a required attribute has no value.
9. valid: It returns true, if an element's value is valid.
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277. ### Give an example usage of rangeOverflow property
If an element's value is greater than its max attribute then rangeOverflow property returns true. For example, the below form submission throws an error if the value is more than 100,
```html
<input id="age" type="number" max="100" />
<button onclick="myOverflowFunction()">OK</button>
```
```javascript
function myOverflowFunction() {
if (document.getElementById("age").validity.rangeOverflow) {
alert("The mentioned age is not allowed");
}
}
```
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278. ### Is enums feature available in javascript
No, javascript does not natively support enums. But there are different kinds of solutions to simulate them even though they may not provide exact equivalents. For example, you can use freeze or seal on object,
```javascript
var DaysEnum = Object.freeze({"monday":1, "tuesday":2, "wednesday":3, ...})
```
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279. ### What is an enum
An enum is a type restricting variables to one value from a predefined set of constants. JavaScript has no enums but typescript provides built-in enum support.
```javascript
enum Color {
RED, GREEN, BLUE
}
```
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280. ### How do you list all properties of an object
You can use the `Object.getOwnPropertyNames()` method which returns an array of all properties found directly in a given object. Let's the usage of it in an example,
```javascript
const newObject = {
a: 1,
b: 2,
c: 3,
};
console.log(Object.getOwnPropertyNames(newObject));
["a", "b", "c"];
```
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281. ### How do you get property descriptors of an object
You can use the `Object.getOwnPropertyDescriptors()` method which returns all own property descriptors of a given object. The example usage of this method is below,
```javascript
const newObject = {
a: 1,
b: 2,
c: 3,
};
const descriptorsObject = Object.getOwnPropertyDescriptors(newObject);
console.log(descriptorsObject.a.writable); //true
console.log(descriptorsObject.a.configurable); //true
console.log(descriptorsObject.a.enumerable); //true
console.log(descriptorsObject.a.value); // 1
```
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282. ### What are the attributes provided by a property descriptor
A property descriptor is a record which has the following attributes
1. value: The value associated with the property
2. writable: Determines whether the value associated with the property can be changed or not
3. configurable: Returns true if the type of this property descriptor can be changed and if the property can be deleted from the corresponding object.
4. enumerable: Determines whether the property appears during enumeration of the properties on the corresponding object or not.
5. set: A function which serves as a setter for the property
6. get: A function which serves as a getter for the property
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283. ### How do you extend classes
The `extends` keyword is used in class declarations/expressions to create a class which is a child of another class. It can be used to subclass custom classes as well as built-in objects. The syntax would be as below,
```javascript
class ChildClass extends ParentClass { ... }
```
Let's take an example of Square subclass from Polygon parent class,
```javascript
class Square extends Rectangle {
constructor(length) {
super(length, length);
this.name = "Square";
}
get area() {
return this.width * this.height;
}
set area(value) {
this.area = value;
}
}
```
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284. ### How do I modify the url without reloading the page
The `window.location.href` property will be helpful to modify the url but it reloads the page. HTML5 introduced the `history.pushState()` and `history.replaceState()` methods, which allow you to add and modify history entries, respectively. For example, you can use pushState as below,
```javascript
window.history.pushState("page2", "Title", "/page2.html");
```
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285. ### How do you check whether an array includes a particular value or not
The `Array#includes()` method is used to determine whether an array includes a particular value among its entries by returning either true or false. Let's see an example to find an element(numeric and string) within an array.
```javascript
var numericArray = [1, 2, 3, 4];
console.log(numericArray.includes(3)); // true
var stringArray = ["green", "yellow", "blue"];
console.log(stringArray.includes("blue")); //true
```
**[⬆ Back to Top](#table-of-contents)**
286. ### How do you compare scalar arrays
You can use length and every method of arrays to compare two scalar(compared directly using ===) arrays. The combination of these expressions can give the expected result,
```javascript
const arrayFirst = [1, 2, 3, 4, 5];
const arraySecond = [1, 2, 3, 4, 5];
console.log(
arrayFirst.length === arraySecond.length &&
arrayFirst.every((value, index) => value === arraySecond[index])
); // true
```
If you would like to compare arrays irrespective of order then you should sort them before,
```javascript
const arrayFirst = [2, 3, 1, 4, 5];
const arraySecond = [1, 2, 3, 4, 5];
console.log(
arrayFirst.length === arraySecond.length &&
arrayFirst.sort().every((value, index) => value === arraySecond[index])
); //true
```
**[⬆ Back to Top](#table-of-contents)**
287. ### How to get the value from get parameters
The `new URL()` object accepts the url string and `searchParams` property of this object can be used to access the get parameters. Remember that you may need to use polyfill or `window.location` to access the URL in older browsers(including IE).
```javascript
let urlString = "http://www.some-domain.com/about.html?x=1&y=2&z=3"; //window.location.href
let url = new URL(urlString);
let parameterZ = url.searchParams.get("z");
console.log(parameterZ); // 3
```
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288. ### How do you print numbers with commas as thousand separators
You can use the `Number.prototype.toLocaleString()` method which returns a string with a language-sensitive representation such as thousand separator,currency etc of this number.
```javascript
function convertToThousandFormat(x) {
return x.toLocaleString(); // 12,345.679
}
console.log(convertToThousandFormat(12345.6789));
```
**[⬆ Back to Top](#table-of-contents)**
289. ### What is the difference between java and javascript
Both are totally unrelated programming languages and no relation between them. Java is statically typed, compiled, runs on its own VM. Whereas Javascript is dynamically typed, interpreted, and runs in a browser and nodejs environments. Let's see the major differences in a tabular format,
| Feature | Java | JavaScript |
|---- | ---- | -----
| Typed | It's a strongly typed language | It's a dynamic typed language |
| Paradigm | Object oriented programming | Prototype based programming |
| Scoping | Block scoped | Function-scoped |
| Concurrency | Thread based | event based |
| Memory | Uses more memory | Uses less memory. Hence it will be used for web pages |
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290. ### Does JavaScript supports namespace
JavaScript doesn’t support namespace by default. So if you create any element(function, method, object, variable) then it becomes global and pollutes the global namespace. Let's take an example of defining two functions without any namespace,
```javascript
function func1() {
console.log("This is a first definition");
}
function func1() {
console.log("This is a second definition");
}
func1(); // This is a second definition
```
It always calls the second function definition. In this case, namespace will solve the name collision problem.
**[⬆ Back to Top](#table-of-contents)**
291. ### How do you declare namespace
Even though JavaScript lacks namespaces, we can use Objects , IIFE to create namespaces.
1. **Using Object Literal Notation:** Let's wrap variables and functions inside an Object literal which acts as a namespace. After that you can access them using object notation
```javascript
var namespaceOne = {
function func1() {
console.log("This is a first definition");
}
}
var namespaceTwo = {
function func1() {
console.log("This is a second definition");
}
}
namespaceOne.func1(); // This is a first definition
namespaceTwo.func1(); // This is a second definition
```
1. **Using IIFE (Immediately invoked function expression):** The outer pair of parentheses of IIFE creates a local scope for all the code inside of it and makes the anonymous function a function expression. Due to that, you can create the same function in two different function expressions to act as a namespace.
```javascript
(function () {
function fun1() {
console.log("This is a first definition");
}
fun1();
})();
(function () {
function fun1() {
console.log("This is a second definition");
}
fun1();
})();
```
1. **Using a block and a let/const declaration:** In ECMAScript 6, you can simply use a block and a let declaration to restrict the scope of a variable to a block.
```javascript
{
let myFunction = function fun1() {
console.log("This is a first definition");
};
myFunction();
}
//myFunction(): ReferenceError: myFunction is not defined.
{
let myFunction = function fun1() {
console.log("This is a second definition");
};
myFunction();
}
//myFunction(): ReferenceError: myFunction is not defined.
```
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292. ### How do you invoke javascript code in an iframe from parent page
Initially iFrame needs to be accessed using either `document.getElementBy` or `window.frames`. After that `contentWindow` property of iFrame gives the access for targetFunction
```javascript
document.getElementById("targetFrame").contentWindow.targetFunction();
window.frames[0].frameElement.contentWindow.targetFunction(); // Accessing iframe this way may not work in latest versions chrome and firefox
```
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293. ### How do get the timezone offset from date
You can use the `getTimezoneOffset` method of the date object. This method returns the time zone difference, in minutes, from current locale (host system settings) to UTC
```javascript
var offset = new Date().getTimezoneOffset();
console.log(offset); // -480
```
**[⬆ Back to Top](#table-of-contents)**
294. ### How do you load CSS and JS files dynamically
You can create both link and script elements in the DOM and append them as child to head tag. Let's create a function to add script and style resources as below,
```javascript
function loadAssets(filename, filetype) {
if (filetype == "css") {
// External CSS file
var fileReference = document.createElement("link");
fileReference.setAttribute("rel", "stylesheet");
fileReference.setAttribute("type", "text/css");
fileReference.setAttribute("href", filename);
} else if (filetype == "js") {
// External JavaScript file
var fileReference = document.createElement("script");
fileReference.setAttribute("type", "text/javascript");
fileReference.setAttribute("src", filename);
}
if (typeof fileReference != "undefined")
document.getElementsByTagName("head")[0].appendChild(fileReference);
}
```
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295. ### What are the different methods to find HTML elements in DOM
If you want to access any element in an HTML page, you need to start with accessing the document object. Later you can use any of the below methods to find the HTML element,
1. document.getElementById(id): It finds an element by Id
2. document.getElementsByTagName(name): It finds an element by tag name
3. document.getElementsByClassName(name): It finds an element by class name
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296. ### What is jQuery
jQuery is a popular cross-browser JavaScript library that provides Document Object Model (DOM) traversal, event handling, animations and AJAX interactions by minimizing the discrepancies across browsers. It is widely famous with its philosophy of “Write less, do more”. For example, you can display welcome message on the page load using jQuery as below,
```javascript
$(document).ready(function () {
// It selects the document and apply the function on page load
alert("Welcome to jQuery world");
});
```
**Note:** You can download it from jquery's official site or install it from CDNs, like google.
**[⬆ Back to Top](#table-of-contents)**
297. ### What is V8 JavaScript engine
V8 is an open source high-performance JavaScript engine used by the Google Chrome browser, written in C++. It is also being used in the node.js project. It implements ECMAScript and WebAssembly, and runs on Windows 7 or later, macOS 10.12+, and Linux systems that use x64, IA-32, ARM, or MIPS processors.
**Note:** It can run standalone, or can be embedded into any C++ application.
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298. ### Why do we call javascript as dynamic language
JavaScript is a loosely typed or a dynamic language because variables in JavaScript are not directly associated with any particular value type, and any variable can be assigned/reassigned with values of all types.
```javascript
let age = 50; // age is a number now
age = "old"; // age is a string now
age = true; // age is a boolean
```
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299. ### What is a void operator
The `void` operator evaluates the given expression and then returns undefined(i.e, without returning value). The syntax would be as below,
```javascript
void expression;
void expression;
```
Let's display a message without any redirection or reload
```javascript
<a href="javascript:void(alert('Welcome to JS world'))">
Click here to see a message
</a>
```
**Note:** This operator is often used to obtain the undefined primitive value, using "void(0)".
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300. ### How to set the cursor to wait
The cursor can be set to wait in JavaScript by using the property "cursor". Let's perform this behavior on page load using the below function.
```javascript
function myFunction() {
window.document.body.style.cursor = "wait";
}
```
and this function invoked on page load
```html
<body onload="myFunction()"></body>
```
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301. ### How do you create an infinite loop
You can create infinite loops using for and while loops without using any expressions. The for loop construct or syntax is better approach in terms of ESLint and code optimizer tools,
```javascript
for (;;) {}
while (true) {}
```
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302. ### Why do you need to avoid with statement
JavaScript's with statement was intended to provide a shorthand for writing recurring accesses to objects. So it can help reduce file size by reducing the need to repeat a lengthy object reference without performance penalty. Let's take an example where it is used to avoid redundancy when accessing an object several times.
```javascript
a.b.c.greeting = "welcome";
a.b.c.age = 32;
```
Using `with` it turns this into:
```javascript
with (a.b.c) {
greeting = "welcome";
age = 32;
}
```
But this `with` statement creates performance problems since one cannot predict whether an argument will refer to a real variable or to a property inside the with argument.
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303. ### What is the output of below for loops
```javascript
for (var i = 0; i < 4; i++) {
// global scope
setTimeout(() => console.log(i));
}
for (let i = 0; i < 4; i++) {
// block scope
setTimeout(() => console.log(i));
}
```
The output of the above for loops is 4 4 4 4 and 0 1 2 3
**Explanation:** Due to the event queue/loop of javascript, the `setTimeout` callback function is called after the loop has been executed. Since the variable i is declared with the `var` keyword it became a global variable and the value was equal to 4 using iteration when the time `setTimeout` function is invoked. Hence, the output of the first loop is `4 4 4 4`.
Whereas in the second loop, the variable i is declared as the `let` keyword it becomes a block scoped variable and it holds a new value(0, 1 ,2 3) for each iteration. Hence, the output of the first loop is `0 1 2 3`.
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304. ### List down some of the features of ES6
Below are the list of some new features of ES6,
1. Support for constants or immutable variables
2. Block-scope support for variables, constants and functions
3. Arrow functions
4. Default parameters
5. Rest and Spread Parameters
6. Template Literals
7. Multi-line Strings
8. Destructuring Assignment
9. Enhanced Object Literals
10. Promises
11. Classes
12. Modules
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305. ### What is ES6
ES6 is the sixth edition of the javascript language and it was released in June 2015. It was initially known as ECMAScript 6 (ES6) and later renamed to ECMAScript 2015. Almost all the modern browsers support ES6 but for the old browsers there are many transpilers, like Babel.js etc.
**[⬆ Back to Top](#table-of-contents)**
306. ### Can I redeclare let and const variables
No, you cannot redeclare let and const variables. If you do, it throws below error
```bash
Uncaught SyntaxError: Identifier 'someVariable' has already been declared
```
**Explanation:** The variable declaration with `var` keyword refers to a function scope and the variable is treated as if it were declared at the top of the enclosing scope due to hoisting feature. So all the multiple declarations contributing to the same hoisted variable without any error. Let's take an example of re-declaring variables in the same scope for both var and let/const variables.
```javascript
var name = "John";
function myFunc() {
var name = "Nick";
var name = "Abraham"; // Re-assigned in the same function block
alert(name); // Abraham
}
myFunc();
alert(name); // John
```
The block-scoped multi-declaration throws syntax error,
```javascript
let name = "John";
function myFunc() {
let name = "Nick";
let name = "Abraham"; // Uncaught SyntaxError: Identifier 'name' has already been declared
alert(name);
}
myFunc();
alert(name);
```
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307. ### Is const variable makes the value immutable
No, the const variable doesn't make the value immutable. But it disallows subsequent assignments(i.e, You can declare with assignment but can't assign another value later)
```javascript
const userList = [];
userList.push("John"); // Can mutate even though it can't re-assign
console.log(userList); // ['John']
```
**[⬆ Back to Top](#table-of-contents)**
308. ### What are default parameters
In ES5, we need to depend on logical OR operators to handle default values of function parameters. Whereas in ES6, Default function parameters feature allows parameters to be initialized with default values if no value or undefined is passed. Let's compare the behavior with an examples,
```javascript
//ES5
var calculateArea = function (height, width) {
height = height || 50;
width = width || 60;
return width * height;
};
console.log(calculateArea()); //300
```
The default parameters makes the initialization more simpler,
```javascript
//ES6
var calculateArea = function (height = 50, width = 60) {
return width * height;
};
console.log(calculateArea()); //300
```
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309. ### What are template literals
Template literals or template strings are string literals allowing embedded expressions. These are enclosed by the back-tick (`) character instead of double or single quotes.
In ES6, this feature enables using dynamic expressions as below,
```javascript
var greeting = `Welcome to JS World, Mr. ${firstName} ${lastName}.`;
```
In ES5, you need break string like below,
```javascript
var greeting = 'Welcome to JS World, Mr. ' + firstName + ' ' + lastName.`
```
**Note:** You can use multi-line strings and string interpolation features with template literals.
**[⬆ Back to Top](#table-of-contents)**
310. ### How do you write multi-line strings in template literals
In ES5, you would have to use newline escape characters('\\n') and concatenation symbols(+) in order to get multi-line strings.
```javascript
console.log("This is string sentence 1\n" + "This is string sentence 2");
```
Whereas in ES6, You don't need to mention any newline sequence character,
```javascript
console.log(`This is string sentence
'This is string sentence 2`);
```
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311. ### What are nesting templates
The nesting template is a feature supported within template literals syntax to allow inner backticks inside a placeholder ${ } within the template. For example, the below nesting template is used to display the icons based on user permissions whereas outer template checks for platform type,
```javascript
const iconStyles = `icon ${
isMobilePlatform()
? ""
: `icon-${user.isAuthorized ? "submit" : "disabled"}`
}`;
```
You can write the above use case without nesting template features as well. However, the nesting template feature is more compact and readable.
```javascript
//Without nesting templates
const iconStyles = `icon ${ isMobilePlatform() ? '' :
user.isAuthorized ? 'icon-submit' : 'icon-disabled'}`;
```
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312. ### What are tagged templates
Tagged templates are the advanced form of templates in which tags allow you to parse template literals with a function. The tag function accepts the first parameter as an array of strings and remaining parameters as expressions. This function can also return manipulated strings based on parameters. Let's see the usage of this tagged template behavior of an IT professional skill set in an organization,
```javascript
var user1 = "John";
var skill1 = "JavaScript";
var experience1 = 15;
var user2 = "Kane";
var skill2 = "JavaScript";
var experience2 = 5;
function myInfoTag(strings, userExp, experienceExp, skillExp) {
var str0 = strings[0]; // "Mr/Ms. "
var str1 = strings[1]; // " is a/an "
var str2 = strings[2]; // "in"
var expertiseStr;
if (experienceExp > 10) {
expertiseStr = "expert developer";
} else if (skillExp > 5 && skillExp <= 10) {
expertiseStr = "senior developer";
} else {
expertiseStr = "junior developer";
}
return `${str0}${userExp}${str1}${expertiseStr}${str2}${skillExp}`;
}
var output1 = myInfoTag`Mr/Ms. ${user1} is a/an ${experience1} in ${skill1}`;
var output2 = myInfoTag`Mr/Ms. ${user2} is a/an ${experience2} in ${skill2}`;
console.log(output1); // Mr/Ms. John is a/an expert developer in JavaScript
console.log(output2); // Mr/Ms. Kane is a/an junior developer in JavaScript
```
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313. ### What are raw strings
ES6 provides a raw strings feature using the `String.raw()` method which is used to get the raw string form of template strings. This feature allows you to access the raw strings as they were entered, without processing escape sequences. For example, the usage would be as below,
```javascript
var calculationString = String.raw`The sum of numbers is \n${
1 + 2 + 3 + 4
}!`;
console.log(calculationString); // The sum of numbers is 10
```
If you don't use raw strings, the newline character sequence will be processed by displaying the output in multiple lines
```javascript
var calculationString = `The sum of numbers is \n${1 + 2 + 3 + 4}!`;
console.log(calculationString);
// The sum of numbers is
// 10
```
Also, the raw property is available on the first argument to the tag function
```javascript
function tag(strings) {
console.log(strings.raw[0]);
}
```
**[⬆ Back to Top](#table-of-contents)**
314. ### What is destructuring assignment
The destructuring assignment is a JavaScript expression that makes it possible to unpack values from arrays or properties from objects into distinct variables.
Let's get the month values from an array using destructuring assignment
```javascript
var [one, two, three] = ["JAN", "FEB", "MARCH"];
console.log(one); // "JAN"
console.log(two); // "FEB"
console.log(three); // "MARCH"
```
and you can get user properties of an object using destructuring assignment,
```javascript
var { name, age } = { name: "John", age: 32 };
console.log(name); // John
console.log(age); // 32
```
**[⬆ Back to Top](#table-of-contents)**
315. ### What are default values in destructuring assignment
A variable can be assigned a default value when the value unpacked from the array or object is undefined during destructuring assignment. It helps to avoid setting default values separately for each assignment. Let's take an example for both arrays and object use cases,
**Arrays destructuring:**
```javascript
var x, y, z;
[x = 2, y = 4, z = 6] = [10];
console.log(x); // 10
console.log(y); // 4
console.log(z); // 6
```
**Objects destructuring:**
```javascript
var { x = 2, y = 4, z = 6 } = { x: 10 };
console.log(x); // 10
console.log(y); // 4
console.log(z); // 6
```
**[⬆ Back to Top](#table-of-contents)**
316. ### How do you swap variables in destructuring assignment
If you don't use destructuring assignment, swapping two values requires a temporary variable. Whereas using a destructuring feature, two variable values can be swapped in one destructuring expression. Let's swap two number variables in array destructuring assignment,
```javascript
var x = 10,
y = 20;
[x, y] = [y, x];
console.log(x); // 20
console.log(y); // 10
```
**[⬆ Back to Top](#table-of-contents)**
317. ### What are enhanced object literals
Object literals make it easy to quickly create objects with properties inside the curly braces. For example, it provides shorter syntax for common object property definition as below.
```javascript
//ES6
var x = 10,
y = 20;
obj = { x, y };
console.log(obj); // {x: 10, y:20}
//ES5
var x = 10,
y = 20;
obj = { x: x, y: y };
console.log(obj); // {x: 10, y:20}
```
**[⬆ Back to Top](#table-of-contents)**
318. ### What are dynamic imports
The dynamic imports using `import()` function syntax allows us to load modules on demand by using promises or the async/await syntax. Currently this feature is in [stage4 proposal](https://github.com/tc39/proposal-dynamic-import). The main advantage of dynamic imports is reduction of our bundle's sizes, the size/payload response of our requests and overall improvements in the user experience.
The syntax of dynamic imports would be as below,
```javascript
import("./Module").then((Module) => Module.method());
```
**[⬆ Back to Top](#table-of-contents)**
319. ### What are the use cases for dynamic imports
Below are some of the use cases of using dynamic imports over static imports,
1. Import a module on-demand or conditionally. For example, if you want to load a polyfill on legacy browser
```javascript
if (isLegacyBrowser()) {
import(···)
.then(···);
}
```
1. Compute the module specifier at runtime. For example, you can use it for internationalization.
```javascript
import(`messages_${getLocale()}.js`).then(···);
```
1. Import a module from within a regular script instead a module.
**[⬆ Back to Top](#table-of-contents)**
320. ### What are typed arrays
Typed arrays are array-like objects from ECMAScript 6 API for handling binary data. JavaScript provides 8 Typed array types,
1. Int8Array: An array of 8-bit signed integers
2. Int16Array: An array of 16-bit signed integers
3. Int32Array: An array of 32-bit signed integers
4. Uint8Array: An array of 8-bit unsigned integers
5. Uint16Array: An array of 16-bit unsigned integers
6. Uint32Array: An array of 32-bit unsigned integers
7. Float32Array: An array of 32-bit floating point numbers
8. Float64Array: An array of 64-bit floating point numbers
For example, you can create an array of 8-bit signed integers as below
```javascript
const a = new Int8Array();
// You can pre-allocate n bytes
const bytes = 1024;
const a = new Int8Array(bytes);
```
**[⬆ Back to Top](#table-of-contents)**
321. ### What are the advantages of module loaders
The module loaders provides the below features,
1. Dynamic loading
2. State isolation
3. Global namespace isolation
4. Compilation hooks
5. Nested virtualization
**[⬆ Back to Top](#table-of-contents)**
322. ### What is collation
Collation is used for sorting a set of strings and searching within a set of strings. It is parameterized by locale and aware of Unicode. Let's take comparison and sorting features,
1. **Comparison:**
```javascript
var list = ["ä", "a", "z"]; // In German, "ä" sorts with "a" Whereas in Swedish, "ä" sorts after "z"
var l10nDE = new Intl.Collator("de");
var l10nSV = new Intl.Collator("sv");
console.log(l10nDE.compare("ä", "z") === -1); // true
console.log(l10nSV.compare("ä", "z") === +1); // true
```
1. **Sorting:**
```javascript
var list = ["ä", "a", "z"]; // In German, "ä" sorts with "a" Whereas in Swedish, "ä" sorts after "z"
var l10nDE = new Intl.Collator("de");
var l10nSV = new Intl.Collator("sv");
console.log(list.sort(l10nDE.compare)); // [ "a", "ä", "z" ]
console.log(list.sort(l10nSV.compare)); // [ "a", "z", "ä" ]
```
**[⬆ Back to Top](#table-of-contents)**
323. ### What is for...of statement
The for...of statement creates a loop iterating over iterable objects or elements such as built-in String, Array, Array-like objects (like arguments or NodeList), TypedArray, Map, Set, and user-defined iterables. The basic usage of for...of statement on arrays would be as below,
```javascript
let arrayIterable = [10, 20, 30, 40, 50];
for (let value of arrayIterable) {
value++;
console.log(value); // 11 21 31 41 51
}
```
**[⬆ Back to Top](#table-of-contents)**
324. ### What is the output of below spread operator array
```javascript
[..."John Resig"];
```
The output of the array is ['J', 'o', 'h', 'n', '', 'R', 'e', 's', 'i', 'g']
**Explanation:** The string is an iterable type and the spread operator within an array maps every character of an iterable to one element. Hence, each character of a string becomes an element within an Array.
**[⬆ Back to Top](#table-of-contents)**
325. ### Is PostMessage secure
Yes, postMessages can be considered very secure as long as the programmer/developer is careful about checking the origin and source of an arriving message. But if you try to send/receive a message without verifying its source will create cross-site scripting attacks.
**[⬆ Back to Top](#table-of-contents)**
326. ### What are the problems with postmessage target origin as wildcard
The second argument of postMessage method specifies which origin is allowed to receive the message. If you use the wildcard “\*” as an argument then any origin is allowed to receive the message. In this case, there is no way for the sender window to know if the target window is at the target origin when sending the message. If the target window has been navigated to another origin, the other origin would receive the data. Hence, this may lead to XSS vulnerabilities.
```javascript
targetWindow.postMessage(message, "*");
```
**[⬆ Back to Top](#table-of-contents)**
327. ### How do you avoid receiving postMessages from attackers
Since the listener listens for any message, an attacker can trick the application by sending a message from the attacker’s origin, which gives an impression that the receiver received the message from the actual sender’s window. You can avoid this issue by validating the origin of the message on the receiver's end using the “message.origin” attribute. For examples, let's check the sender's origin [http://www.some-sender.com](http://www.some-sender.com) on receiver side [www.some-receiver.com](www.some-receiver.com),
```javascript
//Listener on http://www.some-receiver.com/
window.addEventListener("message", function(message){
if(/^http://www\.some-sender\.com$/.test(message.origin)){
console.log('You received the data from valid sender', message.data);
}
});
```
**[⬆ Back to Top](#table-of-contents)**
328. ### Can I avoid using postMessages completely
You cannot avoid using postMessages completely(or 100%). Even though your application doesn’t use postMessage considering the risks, a lot of third party scripts use postMessage to communicate with the third party service. So your application might be using postMessage without your knowledge.
**[⬆ Back to Top](#table-of-contents)**
329. ### Is postMessages synchronous
The postMessages are synchronous in IE8 browser but they are asynchronous in IE9 and all other modern browsers (i.e, IE9+, Firefox, Chrome, Safari).Due to this asynchronous behaviour, we use a callback mechanism when the postMessage is returned.
**[⬆ Back to Top](#table-of-contents)**
330. ### What paradigm is Javascript
JavaScript is a multi-paradigm language, supporting imperative/procedural programming, Object-Oriented Programming and functional programming. JavaScript supports Object-Oriented Programming with prototypical inheritance.
**[⬆ Back to Top](#table-of-contents)**
331. ### What is the difference between internal and external javascript
**Internal JavaScript:** It is the source code within the script tag.
**External JavaScript:** The source code is stored in an external file(stored with .js extension) and referred with in the tag.
**[⬆ Back to Top](#table-of-contents)**
332. ### Is JavaScript faster than server side script
Yes, JavaScript is faster than server side scripts. Because JavaScript is a client-side script it does not require any web server’s help for its computation or calculation. So JavaScript is always faster than any server-side script like ASP, PHP, etc.
**[⬆ Back to Top](#table-of-contents)**
333. ### How do you get the status of a checkbox
You can apply the `checked` property on the selected checkbox in the DOM. If the value is `true` it means the checkbox is checked, otherwise it is unchecked. For example, the below HTML checkbox element can be access using javascript as below:
```html
<input type="checkbox" id="checkboxname" value="Agree" /> Agree the
conditions<br />
```
```javascript
console.log(document.getElementById(‘checkboxname’).checked); // true or false
```
**[⬆ Back to Top](#table-of-contents)**
334. ### What is the purpose of double tilde operator
The double tilde operator(~~) is known as double NOT bitwise operator. This operator is a slightly quicker substitute for Math.floor().
**[⬆ Back to Top](#table-of-contents)**
335. ### How do you convert character to ASCII code
You can use the `String.prototype.charCodeAt()` method to convert string characters to ASCII numbers. For example, let's find ASCII code for the first letter of 'ABC' string,
```javascript
"ABC".charCodeAt(0); // returns 65
```
Whereas `String.fromCharCode()` method converts numbers to equal ASCII characters.
```javascript
String.fromCharCode(65, 66, 67); // returns 'ABC'
```
**[⬆ Back to Top](#table-of-contents)**
336. ### What is ArrayBuffer
An ArrayBuffer object is used to represent a generic, fixed-length raw binary data buffer. You can create it as below,
```javascript
let buffer = new ArrayBuffer(16); // create a buffer of length 16
alert(buffer.byteLength); // 16
```
To manipulate an ArrayBuffer, we need to use a “view” object.
```javascript
//Create a DataView referring to the buffer
let view = new DataView(buffer);
```
**[⬆ Back to Top](#table-of-contents)**
337. ### What is the output of below string expression
```javascript
console.log("Welcome to JS world"[0]);
```
The output of the above expression is "W".
**Explanation:** The bracket notation with specific index on a string returns the character at a specific location. Hence, it returns the character "W" of the string. Since this is not supported in IE7 and below versions, you may need to use the .charAt() method to get the desired result.
**[⬆ Back to Top](#table-of-contents)**
338. ### What is the purpose of Error object
The Error constructor creates an error object and the instances of error objects are thrown when runtime errors occur. The Error object can also be used as a base object for user-defined exceptions. The syntax of error object would be as below,
```javascript
new Error([message[, fileName[, lineNumber]]])
```
You can throw user defined exceptions or errors using Error object in try...catch block as below,
```javascript
try {
if (withdraw > balance)
throw new Error("Oops! You don't have enough balance");
} catch (e) {
console.log(e.name + ": " + e.message);
}
```
**[⬆ Back to Top](#table-of-contents)**
339. ### What is the purpose of EvalError object
The EvalError object indicates an error regarding the global `eval()` function. Even though this exception is not thrown by JavaScript anymore, the EvalError object remains for compatibility. The syntax of this expression would be as below,
```javascript
new EvalError([message[, fileName[, lineNumber]]])
```
You can throw EvalError with in try...catch block as below,
```javascript
try {
throw new EvalError('Eval function error', 'someFile.js', 100);
} catch (e) {
console.log(e.message, e.name, e.fileName); // "Eval function error", "EvalError", "someFile.js"
```
**[⬆ Back to Top](#table-of-contents)**
340. ### What are the list of cases error thrown from non-strict mode to strict mode
When you apply 'use strict'; syntax, some of the below cases will throw a SyntaxError before executing the script
1. When you use Octal syntax
```javascript
var n = 022;
```
1. Using `with` statement
2. When you use delete operator on a variable name
3. Using eval or arguments as variable or function argument name
4. When you use newly reserved keywords
5. When you declare a function in a block
```javascript
if (someCondition) {
function f() {}
}
```
Hence, the errors from above cases are helpful to avoid errors in development/production environments.
**[⬆ Back to Top](#table-of-contents)**
341. ### Do all objects have prototypes
No. All objects have prototypes except for the base object which is created by the user, or an object that is created using the new keyword.
**[⬆ Back to Top](#table-of-contents)**
342. ### What is the difference between a parameter and an argument
Parameter is the variable name of a function definition whereas an argument represents the value given to a function when it is invoked. Let's explain this with a simple function
```javascript
function myFunction(parameter1, parameter2, parameter3) {
console.log(arguments[0]); // "argument1"
console.log(arguments[1]); // "argument2"
console.log(arguments[2]); // "argument3"
}
myFunction("argument1", "argument2", "argument3");
```
**[⬆ Back to Top](#table-of-contents)**
343. ### What is the purpose of some method in arrays
The some() method is used to test whether at least one element in the array passes the test implemented by the provided function. The method returns a boolean value. Let's take an example to test for any odd elements,
```javascript
var array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
var odd = (element) => element % 2 !== 0;
console.log(array.some(odd)); // true (the odd element exists)
```
**[⬆ Back to Top](#table-of-contents)**
344. ### How do you combine two or more arrays
The concat() method is used to join two or more arrays by returning a new array containing all the elements. The syntax would be as below,
```javascript
array1.concat(array2, array3, ..., arrayX)
```
Let's take an example of array's concatenation with veggies and fruits arrays,
```javascript
var veggies = ["Tomato", "Carrot", "Cabbage"];
var fruits = ["Apple", "Orange", "Pears"];
var veggiesAndFruits = veggies.concat(fruits);
console.log(veggiesAndFruits); // Tomato, Carrot, Cabbage, Apple, Orange, Pears
```
**[⬆ Back to Top](#table-of-contents)**
345. ### What is the difference between Shallow and Deep copy
There are two ways to copy an object,
**Shallow Copy:**
Shallow copy is a bitwise copy of an object. A new object is created that has an exact copy of the values in the original object. If any of the fields of the object are references to other objects, just the reference addresses are copied i.e., only the memory address is copied.
**Example**
```javascript
var empDetails = {
name: "John",
age: 25,
expertise: "Software Developer",
};
```
to create a duplicate
```javascript
var empDetailsShallowCopy = empDetails; //Shallow copying!
```
if we change some property value in the duplicate one like this:
```javascript
empDetailsShallowCopy.name = "Johnson";
```
The above statement will also change the name of `empDetails`, since we have a shallow copy. That means we're losing the original data as well.
**Deep copy:**
A deep copy copies all fields, and makes copies of dynamically allocated memory pointed to by the fields. A deep copy occurs when an object is copied along with the objects to which it refers.
**Example**
```javascript
var empDetails = {
name: "John",
age: 25,
expertise: "Software Developer",
};
```
Create a deep copy by using the properties from the original object into new variable
```javascript
var empDetailsDeepCopy = {
name: empDetails.name,
age: empDetails.age,
expertise: empDetails.expertise,
};
```
Now if you change `empDetailsDeepCopy.name`, it will only affect `empDetailsDeepCopy` & not `empDetails`
**[⬆ Back to Top](#table-of-contents)**
346. ### How do you create specific number of copies of a string
The `repeat()` method is used to construct and return a new string which contains the specified number of copies of the string on which it was called, concatenated together. Remember that this method has been added to the ECMAScript 2015 specification.
Let's take an example of Hello string to repeat it 4 times,
```javascript
"Hello".repeat(4); // 'HelloHelloHelloHello'
```
347. ### How do you return all matching strings against a regular expression
The `matchAll()` method can be used to return an iterator of all results matching a string against a regular expression. For example, the below example returns an array of matching string results against a regular expression,
```javascript
let regexp = /Hello(\d?))/g;
let greeting = "Hello1Hello2Hello3";
let greetingList = [...greeting.matchAll(regexp)];
console.log(greetingList[0]); //Hello1
console.log(greetingList[1]); //Hello2
console.log(greetingList[2]); //Hello3
```
**[⬆ Back to Top](#table-of-contents)**
348. ### How do you trim a string at the beginning or ending
The `trim` method of string prototype is used to trim on both sides of a string. But if you want to trim especially at the beginning or ending of the string then you can use `trimStart/trimLeft` and `trimEnd/trimRight` methods. Let's see an example of these methods on a greeting message,
```javascript
var greeting = " Hello, Goodmorning! ";
console.log(greeting); // " Hello, Goodmorning! "
console.log(greeting.trimStart()); // "Hello, Goodmorning! "
console.log(greeting.trimLeft()); // "Hello, Goodmorning! "
console.log(greeting.trimEnd()); // " Hello, Goodmorning!"
console.log(greeting.trimRight()); // " Hello, Goodmorning!"
```
**[⬆ Back to Top](#table-of-contents)**
349. ### What is the output of below console statement with unary operator
Let's take console statement with unary operator as given below,
```javascript
console.log(+"Hello");
```
The output of the above console log statement returns NaN. Because the element is prefixed by the unary operator and the JavaScript interpreter will try to convert that element into a number type. Since the conversion fails, the value of the statement results in NaN value.
**[⬆ Back to Top](#table-of-contents)**
350. ### Does javascript uses mixins
Mixin is a generic object-oriented programming term - is a class containing methods that can be used by other classes without a need to inherit from it. In JavaScript we can only inherit from a single object. ie. There can be only one `[[prototype]]` for an object.
But sometimes we require to extend more than one, to overcome this we can use Mixin which helps to copy methods to the prototype of another class.
Say for instance, we've two classes `User` and `CleanRoom`. Suppose we need to add `CleanRoom` functionality to `User`, so that user can clean the room at demand. Here's where concept called mixins comes into picture.
```javascript
// mixin
let cleanRoomMixin = {
cleanRoom() {
alert(`Hello ${this.name}, your room is clean now`);
},
sayBye() {
alert(`Bye ${this.name}`);
},
};
// usage:
class User {
constructor(name) {
this.name = name;
}
}
// copy the methods
Object.assign(User.prototype, cleanRoomMixin);
// now User can clean the room
new User("Dude").cleanRoom(); // Hello Dude, your room is clean now!
```
**[⬆ Back to Top](#table-of-contents)**
351. ### What is a thunk function
A thunk is just a function which delays the evaluation of the value. It doesn’t take any arguments but gives the value whenever you invoke the thunk. i.e, It is used not to execute now but it will be sometime in the future. Let's take a synchronous example,
```javascript
const add = (x, y) => x + y;
const thunk = () => add(2, 3);
thunk(); // 5
```
**[⬆ Back to Top](#table-of-contents)**
352. ### What are asynchronous thunks
The asynchronous thunks are useful to make network requests. Let's see an example of network requests,
```javascript
function fetchData(fn) {
fetch("https://jsonplaceholder.typicode.com/todos/1")
.then((response) => response.json())
.then((json) => fn(json));
}
const asyncThunk = function () {
return fetchData(function getData(data) {
console.log(data);
});
};
asyncThunk();
```
The `getData` function won't be called immediately but it will be invoked only when the data is available from API endpoint. The setTimeout function is also used to make our code asynchronous. The best real time example is redux state management library which uses the asynchronous thunks to delay the actions to dispatch.
**[⬆ Back to Top](#table-of-contents)**
353. ### What is the output of below function calls
**Code snippet:**
```javascript
const circle = {
radius: 20,
diameter() {
return this.radius * 2;
},
perimeter: () => 2 * Math.PI * this.radius,
};
```
```javascript
console.log(circle.diameter());
console.log(circle.perimeter());
```
**Output:**
The output is 40 and NaN. Remember that diameter is a regular function, whereas the value of perimeter is an arrow function. The `this` keyword of a regular function(i.e, diameter) refers to the surrounding scope which is a class(i.e, Shape object). Whereas this keyword of perimeter function refers to the surrounding scope which is a window object. Since there is no radius property on window objects it returns an undefined value and the multiple of number value returns NaN value.
**[⬆ Back to Top](#table-of-contents)**
354. ### How to remove all line breaks from a string
The easiest approach is using regular expressions to detect and replace newlines in the string. In this case, we use replace function along with string to replace with, which in our case is an empty string.
```javascript
function remove_linebreaks( var message ) {
return message.replace( /[\r\n]+/gm, "" );
}
```
In the above expression, g and m are for global and multiline flags.
**[⬆ Back to Top](#table-of-contents)**
355. ### What is the difference between reflow and repaint
A _repaint_ occurs when changes are made which affect the visibility of an element, but not its layout. Examples of this include outline, visibility, or background color. A _reflow_ involves changes that affect the layout of a portion of the page (or the whole page). Resizing the browser window, changing the font, content changing (such as user typing text), using JavaScript methods involving computed styles, adding or removing elements from the DOM, and changing an element's classes are a few of the things that can trigger reflow. Reflow of an element causes the subsequent reflow of all child and ancestor elements as well as any elements following it in the DOM.
**[⬆ Back to Top](#table-of-contents)**
356. ### What happens with negating an array
Negating an array with `!` character will coerce the array into a boolean. Since Arrays are considered to be truthy So negating it will return `false`.
```javascript
console.log(![]); // false
```
**[⬆ Back to Top](#table-of-contents)**
357. ### What happens if we add two arrays
If you add two arrays together, it will convert them both to strings and concatenate them. For example, the result of adding arrays would be as below,
```javascript
console.log(["a"] + ["b"]); // "ab"
console.log([] + []); // ""
console.log(![] + []); // "false", because ![] returns false.
```
**[⬆ Back to Top](#table-of-contents)**
358. ### What is the output of prepend additive operator on falsy values
If you prepend the additive(+) operator on falsy values(null, undefined, NaN, false, ""), the falsy value converts to a number value zero. Let's display them on browser console as below,
```javascript
console.log(+null); // 0
console.log(+undefined); // NaN
console.log(+false); // 0
console.log(+NaN); // NaN
console.log(+""); // 0
```
**[⬆ Back to Top](#table-of-contents)**
359. ### How do you create self string using special characters
The self string can be formed with the combination of `[]()!+` characters. You need to remember the below conventions to achieve this pattern.
1. Since Arrays are truthful values, negating the arrays will produce false: ![] === false
2. As per JavaScript coercion rules, the addition of arrays together will toString them: [] + [] === ""
3. Prepend an array with + operator will convert an array to false, the negation will make it true and finally converting the result will produce value '1': +(!(+[])) === 1
By applying the above rules, we can derive below conditions
```javascript
(![] + [] === "false" + !+[]) === 1;
```
Now the character pattern would be created as below,
```javascript
s e l f
^^^^^^^^^^^^^ ^^^^^^^^^^^^^ ^^^^^^^^^^^^^ ^^^^^^^^^^^^^
(![] + [])[3] + (![] + [])[4] + (![] + [])[2] + (![] + [])[0]
^^^^^^^^^^^^^ ^^^^^^^^^^^^^ ^^^^^^^^^^^^^ ^^^^^^^^^^^^^
(![] + [])[+!+[]+!+[]+!+[]] +
(![] + [])[+!+[]+!+[]+!+[]+!+[]] +
(![] + [])[+!+[]+!+[]] +
(![] + [])[+[]]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
(![]+[])[+!+[]+!+[]+!+[]]+(![]+[])[+!+[]+!+[]+!+[]+!+[]]+(![]+[])[+!+[]+!+[]]+(![]+[])[+[]]
```
**[⬆ Back to Top](#table-of-contents)**
360. ### How do you remove falsy values from an array
You can apply the filter method on the array by passing Boolean as a parameter. This way it removes all falsy values(0, undefined, null, false and "") from the array.
```javascript
const myArray = [false, null, 1, 5, undefined];
myArray.filter(Boolean); // [1, 5] // is same as myArray.filter(x => x);
```
**[⬆ Back to Top](#table-of-contents)**
361. ### How do you get unique values of an array
You can get unique values of an array with the combination of `Set` and rest expression/spread(...) syntax.
```javascript
console.log([...new Set([1, 2, 4, 4, 3])]); // [1, 2, 4, 3]
```
**[⬆ Back to Top](#table-of-contents)**
362. ### What is destructuring aliases
Sometimes you would like to have a destructured variable with a different name than the property name. In that case, you'll use a `: newName` to specify a name for the variable. This process is called destructuring aliases.
```javascript
const obj = { x: 1 };
// Grabs obj.x as as { otherName }
const { x: otherName } = obj;
```
**[⬆ Back to Top](#table-of-contents)**
363. ### How do you map the array values without using map method
You can map the array values without using the `map` method by just using the `from` method of Array. Let's map city names from Countries array,
```javascript
const countries = [
{ name: "India", capital: "Delhi" },
{ name: "US", capital: "Washington" },
{ name: "Russia", capital: "Moscow" },
{ name: "Singapore", capital: "Singapore" },
{ name: "China", capital: "Beijing" },
{ name: "France", capital: "Paris" },
];
const cityNames = Array.from(countries, ({ capital }) => capital);
console.log(cityNames); // ['Delhi, 'Washington', 'Moscow', 'Singapore', 'Beijing', 'Paris']
```
**[⬆ Back to Top](#table-of-contents)**
364. ### How do you empty an array
You can empty an array quickly by setting the array length to zero.
```javascript
let cities = ["Singapore", "Delhi", "London"];
cities.length = 0; // cities becomes []
```
**[⬆ Back to Top](#table-of-contents)**
365. ### How do you rounding numbers to certain decimals
You can round numbers to a certain number of decimals using `toFixed` method from native javascript.
```javascript
let pie = 3.141592653;
pie = pie.toFixed(3); // 3.142
```
**[⬆ Back to Top](#table-of-contents)**
366. ### What is the easiest way to convert an array to an object
You can convert an array to an object with the same data using spread(...) operator.
```javascript
var fruits = ["banana", "apple", "orange", "watermelon"];
var fruitsObject = { ...fruits };
console.log(fruitsObject); // {0: "banana", 1: "apple", 2: "orange", 3: "watermelon"}
```
**[⬆ Back to Top](#table-of-contents)**
367. ### How do you create an array with some data
You can create an array with some data or an array with the same values using `fill` method.
```javascript
var newArray = new Array(5).fill("0");
console.log(newArray); // ["0", "0", "0", "0", "0"]
```
**[⬆ Back to Top](#table-of-contents)**
368. ### What are the placeholders from console object
Below are the list of placeholders available from console object,
1. %o — It takes an object,
2. %s — It takes a string,
3. %d — It is used for a decimal or integer
These placeholders can be represented in the console.log as below
```javascript
const user = { name: "John", id: 1, city: "Delhi" };
console.log(
"Hello %s, your details %o are available in the object form",
"John",
user
); // Hello John, your details {name: "John", id: 1, city: "Delhi"} are available in object
```
**[⬆ Back to Top](#table-of-contents)**
369. ### Is it possible to add CSS to console messages
Yes, you can apply CSS styles to console messages similar to html text on the web page.
```javascript
console.log(
"%c The text has blue color, with large font and red background",
"color: blue; font-size: x-large; background: red"
);
```
The text will be displayed as below,
**Note:** All CSS styles can be applied to console messages.
**[⬆ Back to Top](#table-of-contents)**
370. ### What is the purpose of dir method of console object
The `console.dir()` is used to display an interactive list of the properties of the specified JavaScript object as JSON.
```javascript
const user = { name: "John", id: 1, city: "Delhi" };
console.dir(user);
```
The user object displayed in JSON representation
**[⬆ Back to Top](#table-of-contents)**
371. ### Is it possible to debug HTML elements in console
Yes, it is possible to get and debug HTML elements in the console just like inspecting elements.
```javascript
const element = document.getElementsByTagName("body")[0];
console.log(element);
```
It prints the HTML element in the console,
**[⬆ Back to Top](#table-of-contents)**
372. ### How do you display data in a tabular format using console object
The `console.table()` is used to display data in the console in a tabular format to visualize complex arrays or objects.
```js
const users = [
{ name: "John", id: 1, city: "Delhi" },
{ name: "Max", id: 2, city: "London" },
{ name: "Rod", id: 3, city: "Paris" },
];
console.table(users);
```
The data visualized in a table format,
**Not:** Remember that `console.table()` is not supported in IE.
**[⬆ Back to Top](#table-of-contents)**
373. ### How do you verify that an argument is a Number or not
The combination of IsNaN and isFinite methods are used to confirm whether an argument is a number or not.
```javascript
function isNumber(n) {
return !isNaN(parseFloat(n)) && isFinite(n);
}
```
**[⬆ Back to Top](#table-of-contents)**
374. ### How do you create copy to clipboard button
You need to select the content(using .select() method) of the input element and execute the copy command with execCommand (i.e, execCommand('copy')). You can also execute other system commands like cut and paste.
```javascript
document.querySelector("#copy-button").onclick = function () {
// Select the content
document.querySelector("#copy-input").select();
// Copy to the clipboard
document.execCommand("copy");
};
```
**[⬆ Back to Top](#table-of-contents)**
375. ### What is the shortcut to get timestamp
You can use `new Date().getTime()` to get the current timestamp. There is an alternative shortcut to get the value.
```javascript
console.log(+new Date());
console.log(Date.now());
```
**[⬆ Back to Top](#table-of-contents)**
376. ### How do you flattening multi dimensional arrays
Flattening bi-dimensional arrays is trivial with Spread operator.
```javascript
const biDimensionalArr = [11, [22, 33], [44, 55], [66, 77], 88, 99];
const flattenArr = [].concat(...biDimensionalArr); // [11, 22, 33, 44, 55, 66, 77, 88, 99]
```
But you can make it work with multi-dimensional arrays by recursive calls,
```javascript
function flattenMultiArray(arr) {
const flattened = [].concat(...arr);
return flattened.some((item) => Array.isArray(item))
? flattenMultiArray(flattened)
: flattened;
}
const multiDimensionalArr = [11, [22, 33], [44, [55, 66, [77, [88]], 99]]];
const flatArr = flattenMultiArray(multiDimensionalArr); // [11, 22, 33, 44, 55, 66, 77, 88, 99]
```
Also you can use the `flat` method of Array.
```javascript
const arr = [1, [2,3], 4, 5, [6,7]];
const fllattenArr = arr.flat(); // [1, 2, 3, 4, 5, 6, 7]
// And for multiDemensional arrays
const multiDimensionalArr = [11, [22, 33], [44, [55, 66, [77, [88]], 99]]];
const oneStepFlat = multiDimensionalArr.flat(1); // [11, 22, 33, 44, [55, 66, [77, [88]], 99]]
const towStep = multiDimensionalArr.flat(2); // [11, 22, 33, 44, 55, 66, [77, [88]], 99]
const fullyFlatArray = multiDimensionalArr.flat(Infinity); // [11, 22, 33, 44, 55, 66, 77, 88, 99]
```
**[⬆ Back to Top](#table-of-contents)**
377. ### What is the easiest multi condition checking
You can use `indexOf` to compare input with multiple values instead of checking each value as one condition.
```javascript
// Verbose approach
if (
input === "first" ||
input === 1 ||
input === "second" ||
input === 2
) {
someFunction();
}
// Shortcut
if (["first", 1, "second", 2].indexOf(input) !== -1) {
someFunction();
}
```
**[⬆ Back to Top](#table-of-contents)**
378. ### How do you capture browser back button
The `window.onbeforeunload` method is used to capture browser back button events. This is helpful to warn users about losing the current data.
```javascript
window.onbeforeunload = function () {
alert("You work will be lost");
};
```
**[⬆ Back to Top](#table-of-contents)**
379. ### How do you disable right click in the web page
The right click on the page can be disabled by returning false from the `oncontextmenu` attribute on the body element.
```html
<body oncontextmenu="return false;"></body>
```
**[⬆ Back to Top](#table-of-contents)**
380. ### What are wrapper objects
Primitive Values like string,number and boolean don't have properties and methods but they are temporarily converted or coerced to an object(Wrapper object) when you try to perform actions on them. For example, if you apply toUpperCase() method on a primitive string value, it does not throw an error but returns uppercase of the string.
```javascript
let name = "john";
console.log(name.toUpperCase()); // Behind the scenes treated as console.log(new String(name).toUpperCase());
```
i.e, Every primitive except null and undefined have Wrapper Objects and the list of wrapper objects are String,Number,Boolean,Symbol and BigInt.
**[⬆ Back to Top](#table-of-contents)**
381. ### What is AJAX
AJAX stands for Asynchronous JavaScript and XML and it is a group of related technologies(HTML, CSS, JavaScript, XMLHttpRequest API etc) used to display data asynchronously. i.e. We can send data to the server and get data from the server without reloading the web page.
**[⬆ Back to Top](#table-of-contents)**
382. ### What are the different ways to deal with Asynchronous Code
Below are the list of different ways to deal with Asynchronous code.
1. Callbacks
2. Promises
3. Async/await
4. Third-party libraries such as async.js,bluebird etc
**[⬆ Back to Top](#table-of-contents)**
383. ### How to cancel a fetch request
Until a few days back, One shortcoming of native promises is no direct way to cancel a fetch request. But the new `AbortController` from js specification allows you to use a signal to abort one or multiple fetch calls.
The basic flow of cancelling a fetch request would be as below,
1. Create an `AbortController` instance
2. Get the signal property of an instance and pass the signal as a fetch option for signal
3. Call the AbortController's abort property to cancel all fetches that use that signal
For example, let's pass the same signal to multiple fetch calls will cancel all requests with that signal,
```javascript
const controller = new AbortController();
const { signal } = controller;
fetch("http://localhost:8000", { signal })
.then((response) => {
console.log(`Request 1 is complete!`);
})
.catch((e) => {
if (e.name === "AbortError") {
// We know it's been canceled!
}
});
fetch("http://localhost:8000", { signal })
.then((response) => {
console.log(`Request 2 is complete!`);
})
.catch((e) => {
if (e.name === "AbortError") {
// We know it's been canceled!
}
});
// Wait 2 seconds to abort both requests
setTimeout(() => controller.abort(), 2000);
```
**[⬆ Back to Top](#table-of-contents)**
384. ### What is web speech API
Web speech API is used to enable modern browsers recognize and synthesize speech(i.e, voice data into web apps). This API has been introduced by W3C Community in the year 2012. It has two main parts,
1. **SpeechRecognition (Asynchronous Speech Recognition or Speech-to-Text):** It provides the ability to recognize voice context from an audio input and respond accordingly. This is accessed by the `SpeechRecognition` interface.
The below example shows on how to use this API to get text from speech,
```javascript
window.SpeechRecognition =
window.webkitSpeechRecognition || window.SpeechRecognition; // webkitSpeechRecognition for Chrome and SpeechRecognition for FF
const recognition = new window.SpeechRecognition();
recognition.onresult = (event) => {
// SpeechRecognitionEvent type
const speechToText = event.results[0][0].transcript;
console.log(speechToText);
};
recognition.start();
```
In this API, browser is going to ask you for permission to use your microphone
1. **SpeechSynthesis (Text-to-Speech):** It provides the ability to recognize voice context from an audio input and respond. This is accessed by the `SpeechSynthesis` interface.
For example, the below code is used to get voice/speech from text,
```javascript
if ("speechSynthesis" in window) {
var speech = new SpeechSynthesisUtterance("Hello World!");
speech.lang = "en-US";
window.speechSynthesis.speak(speech);
}
```
The above examples can be tested on chrome(33+) browser's developer console.
**Note:** This API is still a working draft and only available in Chrome and Firefox browsers(ofcourse Chrome only implemented the specification)
**[⬆ Back to Top](#table-of-contents)**
385. ### What is minimum timeout throttling
Both browser and NodeJS javascript environments throttles with a minimum delay that is greater than 0ms. That means even though setting a delay of 0ms will not happen instantaneously.
**Browsers:** They have a minimum delay of 4ms. This throttle occurs when successive calls are triggered due to callback nesting(certain depth) or after a certain number of successive intervals.
Note: The older browsers have a minimum delay of 10ms.
**Nodejs:** They have a minimum delay of 1ms. This throttle happens when the delay is larger than 2147483647 or less than 1.
The best example to explain this timeout throttling behavior is the order of below code snippet.
```javascript
function runMeFirst() {
console.log("My script is initialized");
}
setTimeout(runMeFirst, 0);
console.log("Script loaded");
```
and the output would be in
```cmd
Script loaded
My script is initialized
```
If you don't use `setTimeout`, the order of logs will be sequential.
```javascript
function runMeFirst() {
console.log("My script is initialized");
}
runMeFirst();
console.log("Script loaded");
```
and the output is,
```cmd
My script is initialized
Script loaded
```
**[⬆ Back to Top](#table-of-contents)**
386. ### How do you implement zero timeout in modern browsers
You can't use setTimeout(fn, 0) to execute the code immediately due to minimum delay of greater than 0ms. But you can use window.postMessage() to achieve this behavior.
**[⬆ Back to Top](#table-of-contents)**
387. ### What are tasks in event loop
A task is any javascript code/program which is scheduled to be run by the standard mechanisms such as initially starting to run a program, run an event callback, or an interval or timeout being fired. All these tasks are scheduled on a task queue.
Below are the list of use cases to add tasks to the task queue,
1. When a new javascript program is executed directly from console or running by the `<script>` element, the task will be added to the task queue.
2. When an event fires, the event callback added to task queue
3. When a setTimeout or setInterval is reached, the corresponding callback added to task queue
**[⬆ Back to Top](#table-of-contents)**
388. ### What is microtask
Microtask is the javascript code which needs to be executed immediately after the currently executing task/microtask is completed. They are kind of blocking in nature. i.e, The main thread will be blocked until the microtask queue is empty.
The main sources of microtasks are Promise.resolve, Promise.reject, MutationObservers, IntersectionObservers etc
**Note:** All of these microtasks are processed in the same turn of the event loop.
**[⬆ Back to Top](#table-of-contents)**
389. ### What are different event loops
In JavaScript, there are multiple event loops that can be used depending on the context of your application. The most common event loops are:
1. The Browser Event Loop
2. The Node.js Event Loop
- Browser Event Loop: The Browser Event Loop is used in client-side JavaScript applications and is responsible for handling events that occur within the browser environment, such as user interactions (clicks, keypresses, etc.), HTTP requests, and other asynchronous actions.
- The Node.js Event Loop is used in server-side JavaScript applications and is responsible for handling events that occur within the Node.js runtime environment, such as file I/O, network I/O, and other asynchronous actions.
**[⬆ Back to Top](#table-of-contents)**
390. ### What is the purpose of queueMicrotask
The `queueMicrotask` function is used to schedule a microtask, which is a function that will be executed asynchronously in the microtask queue. The purpose of `queueMicrotask` is to ensure that a function is executed after the current task has finished, but before the browser performs any rendering or handles user events.
Example:
```javascript
console.log('Start'); //1
queueMicrotask(() => {
console.log('Inside microtask'); // 3
});
console.log('End'); //2
```
By using queueMicrotask, you can ensure that certain tasks or callbacks are executed at the earliest opportunity during the JavaScript event loop, making it useful for performing work that needs to be done asynchronously but with higher priority than regular `setTimeout` or `setInterval` callbacks.
**[⬆ Back to Top](#table-of-contents)**
391. ### How do you use javascript libraries in typescript file
It is known that not all JavaScript libraries or frameworks have TypeScript declaration files. But if you still want to use libraries or frameworks in our TypeScript files without getting compilation errors, the only solution is `declare` keyword along with a variable declaration. For example, let's imagine you have a library called `customLibrary` that doesn’t have a TypeScript declaration and have a namespace called `customLibrary` in the global namespace. You can use this library in typescript code as below,
```javascript
declare var customLibrary;
```
In the runtime, typescript will provide the type to the `customLibrary` variable as `any` type. The another alternative without using declare keyword is below
```javascript
var customLibrary: any;
```
**[⬆ Back to Top](#table-of-contents)**
392. ### What are the differences between promises and observables
Some of the major difference in a tabular form
| Promises | Observables |
| ------------------------------------------------------------------ | ---------------------------------------------------------------------------------------- |
| Emits only a single value at a time | Emits multiple values over a period of time(stream of values ranging from 0 to multiple) |
| Eager in nature; they are going to be called immediately | Lazy in nature; they require subscription to be invoked |
| Promise is always asynchronous even though it resolved immediately | Observable can be either synchronous or asynchronous |
| Doesn't provide any operators | Provides operators such as map, forEach, filter, reduce, retry, and retryWhen etc |
| Cannot be canceled | Canceled by using unsubscribe() method |
**[⬆ Back to Top](#table-of-contents)**
393. ### What is heap
Heap(Or memory heap) is the memory location where objects are stored when we define variables. i.e, This is the place where all the memory allocations and de-allocation take place. Both heap and call-stack are two containers of JS runtime.
Whenever runtime comes across variables and function declarations in the code it stores them in the Heap.
**[⬆ Back to Top](#table-of-contents)**
394. ### What is an event table
Event Table is a data structure that stores and keeps track of all the events which will be executed asynchronously like after some time interval or after the resolution of some API requests. i.e Whenever you call a setTimeout function or invoke async operation, it is added to the Event Table.
It doesn't not execute functions on it’s own. The main purpose of the event table is to keep track of events and send them to the Event Queue as shown in the below diagram.
**[⬆ Back to Top](#table-of-contents)**
395. ### What is a microTask queue
Microtask Queue is the new queue where all the tasks initiated by promise objects get processed before the callback queue.
The microtasks queue are processed before the next rendering and painting jobs. But if these microtasks are running for a long time then it leads to visual degradation.
**[⬆ Back to Top](#table-of-contents)**
396. ### What is the difference between shim and polyfill
A shim is a library that brings a new API to an older environment, using only the means of that environment. It isn't necessarily restricted to a web application. For example, es5-shim.js is used to emulate ES5 features on older browsers (mainly pre IE9).
Whereas polyfill is a piece of code (or plugin) that provides the technology that you, the developer, expect the browser to provide natively.
In a simple sentence, A polyfill is a shim for a browser API.
**[⬆ Back to Top](#table-of-contents)**
397. ### How do you detect primitive or non primitive value type
In JavaScript, primitive types include boolean, string, number, BigInt, null, Symbol and undefined. Whereas non-primitive types include the Objects. But you can easily identify them with the below function,
```javascript
var myPrimitive = 30;
var myNonPrimitive = {};
function isPrimitive(val) {
return Object(val) !== val;
}
isPrimitive(myPrimitive);
isPrimitive(myNonPrimitive);
```
If the value is a primitive data type, the Object constructor creates a new wrapper object for the value. But If the value is a non-primitive data type (an object), the Object constructor will give the same object.
**[⬆ Back to Top](#table-of-contents)**
398. ### What is babel
Babel is a JavaScript transpiler to convert ECMAScript 2015+ code into a backwards compatible version of JavaScript in current and older browsers or environments. Some of the main features are listed below,
1. Transform syntax
2. Polyfill features that are missing in your target environment (using @babel/polyfill)
3. Source code transformations (or codemods)
**[⬆ Back to Top](#table-of-contents)**
399. ### Is Node.js completely single threaded
Node is a single thread, but some of the functions included in the Node.js standard library(e.g, fs module functions) are not single threaded. i.e, Their logic runs outside of the Node.js single thread to improve the speed and performance of a program.
**[⬆ Back to Top](#table-of-contents)**
400. ### What are the common use cases of observables
Some of the most common use cases of observables are web sockets with push notifications, user input changes, repeating intervals, etc
**[⬆ Back to Top](#table-of-contents)**
401. ### What is RxJS
RxJS (Reactive Extensions for JavaScript) is a library for implementing reactive programming using observables that makes it easier to compose asynchronous or callback-based code. It also provides utility functions for creating and working with observables.
**[⬆ Back to Top](#table-of-contents)**
402. ### What is the difference between Function constructor and function declaration
The functions which are created with `Function constructor` do not create closures to their creation contexts but they are always created in the global scope. i.e, the function can access its own local variables and global scope variables only. Whereas function declarations can access outer function variables(closures) too.
Let's see this difference with an example,
**Function Constructor:**
```javascript
var a = 100;
function createFunction() {
var a = 200;
return new Function("return a;");
}
console.log(createFunction()()); // 100
```
**Function declaration:**
```javascript
var a = 100;
function createFunction() {
var a = 200;
return function func() {
return a;
};
}
console.log(createFunction()()); // 200
```
**[⬆ Back to Top](#table-of-contents)**
403. ### What is a Short circuit condition
Short circuit conditions are meant for condensed way of writing simple if statements. Let's demonstrate the scenario using an example. If you would like to login to a portal with an authentication condition, the expression would be as below,
```javascript
if (authenticate) {
loginToPorta();
}
```
Since the javascript logical operators evaluated from left to right, the above expression can be simplified using && logical operator
```javascript
authenticate && loginToPorta();
```
**[⬆ Back to Top](#table-of-contents)**
404. ### What is the easiest way to resize an array
The length property of an array is useful to resize or empty an array quickly. Let's apply length property on number array to resize the number of elements from 5 to 2,
```javascript
var array = [1, 2, 3, 4, 5];
console.log(array.length); // 5
array.length = 2;
console.log(array.length); // 2
console.log(array); // [1,2]
```
and the array can be emptied too
```javascript
var array = [1, 2, 3, 4, 5];
array.length = 0;
console.log(array.length); // 0
console.log(array); // []
```
**[⬆ Back to Top](#table-of-contents)**
405. ### What is an observable
An Observable is basically a function that can return a stream of values either synchronously or asynchronously to an observer over time. The consumer can get the value by calling `subscribe()` method.
Let's look at a simple example of an Observable
```javascript
import { Observable } from "rxjs";
const observable = new Observable((observer) => {
setTimeout(() => {
observer.next("Message from a Observable!");
}, 3000);
});
observable.subscribe((value) => console.log(value));
```
**Note:** Observables are not part of the JavaScript language yet but they are being proposed to be added to the language
**[⬆ Back to Top](#table-of-contents)**
406. ### What is the difference between function and class declarations
The main difference between function declarations and class declarations is `hoisting`. The function declarations are hoisted but not class declarations.
**Classes:**
```javascript
const user = new User(); // ReferenceError
class User {}
```
**Constructor Function:**
```javascript
const user = new User(); // No error
function User() {}
```
**[⬆ Back to Top](#table-of-contents)**
407. ### What is an async function
An async function is a function declared with the `async` keyword which enables asynchronous, promise-based behavior to be written in a cleaner style by avoiding promise chains. These functions can contain zero or more `await` expressions.
Let's take a below async function example,
```javascript
async function logger() {
let data = await fetch("http://someapi.com/users"); // pause until fetch returns
console.log(data);
}
logger();
```
It is basically syntax sugar over ES2015 promises and generators.
**[⬆ Back to Top](#table-of-contents)**
408. ### How do you prevent promises swallowing errors
While using asynchronous code, JavaScript’s ES6 promises can make your life a lot easier without having callback pyramids and error handling on every second line. But Promises have some pitfalls and the biggest one is swallowing errors by default.
Let's say you expect to print an error to the console for all the below cases,
```javascript
Promise.resolve("promised value").then(function () {
throw new Error("error");
});
Promise.reject("error value").catch(function () {
throw new Error("error");
});
new Promise(function (resolve, reject) {
throw new Error("error");
});
```
But there are many modern JavaScript environments that won't print any errors. You can fix this problem in different ways,
1. **Add catch block at the end of each chain:** You can add catch block to the end of each of your promise chains
```javascript
Promise.resolve("promised value")
.then(function () {
throw new Error("error");
})
.catch(function (error) {
console.error(error.stack);
});
```
But it is quite difficult to type for each promise chain and verbose too.
2. **Add done method:** You can replace first solution's then and catch blocks with done method
```javascript
Promise.resolve("promised value").done(function () {
throw new Error("error");
});
```
Let's say you want to fetch data using HTTP and later perform processing on the resulting data asynchronously. You can write `done` block as below,
```javascript
getDataFromHttp()
.then(function (result) {
return processDataAsync(result);
})
.done(function (processed) {
displayData(processed);
});
```
In future, if the processing library API changed to synchronous then you can remove `done` block as below,
```javascript
getDataFromHttp().then(function (result) {
return displayData(processDataAsync(result));
});
```
and then you forgot to add `done` block to `then` block leads to silent errors.
3. **Extend ES6 Promises by Bluebird:**
Bluebird extends the ES6 Promises API to avoid the issue in the second solution. This library has a “default” onRejection handler which will print all errors from rejected Promises to stderr. After installation, you can process unhandled rejections
```javascript
Promise.onPossiblyUnhandledRejection(function (error) {
throw error;
});
```
and discard a rejection, just handle it with an empty catch
```javascript
Promise.reject("error value").catch(function () {});
```
**[⬆ Back to Top](#table-of-contents)**
409. ### What is deno
Deno is a simple, modern and secure runtime for JavaScript and TypeScript that uses V8 JavaScript engine and the Rust programming language.
**[⬆ Back to Top](#table-of-contents)**
410. ### How do you make an object iterable in javascript
By default, plain objects are not iterable. But you can make the object iterable by defining a `Symbol.iterator` property on it.
Let's demonstrate this with an example,
```javascript
const collection = {
one: 1,
two: 2,
three: 3,
[Symbol.iterator]() {
const values = Object.keys(this);
let i = 0;
return {
next: () => {
return {
value: this[values[i++]],
done: i > values.length,
};
},
};
},
};
const iterator = collection[Symbol.iterator]();
console.log(iterator.next()); // → {value: 1, done: false}
console.log(iterator.next()); // → {value: 2, done: false}
console.log(iterator.next()); // → {value: 3, done: false}
console.log(iterator.next()); // → {value: undefined, done: true}
```
The above process can be simplified using a generator function,
```javascript
const collection = {
one: 1,
two: 2,
three: 3,
[Symbol.iterator]: function* () {
for (let key in this) {
yield this[key];
}
},
};
const iterator = collection[Symbol.iterator]();
console.log(iterator.next()); // {value: 1, done: false}
console.log(iterator.next()); // {value: 2, done: false}
console.log(iterator.next()); // {value: 3, done: false}
console.log(iterator.next()); // {value: undefined, done: true}
```
**[⬆ Back to Top](#table-of-contents)**
411. ### What is a Proper Tail Call
First, we should know about tail call before talking about "Proper Tail Call". A tail call is a subroutine or function call performed as the final action of a calling function. Whereas **Proper tail call(PTC)** is a technique where the program or code will not create additional stack frames for a recursion when the function call is a tail call.
For example, the below classic or head recursion of factorial function relies on stack for each step. Each step need to be processed upto `n * factorial(n - 1)`
```javascript
function factorial(n) {
if (n === 0) {
return 1;
}
return n * factorial(n - 1);
}
console.log(factorial(5)); //120
```
But if you use Tail recursion functions, they keep passing all the necessary data it needs down the recursion without relying on the stack.
```javascript
function factorial(n, acc = 1) {
if (n === 0) {
return acc;
}
return factorial(n - 1, n * acc);
}
console.log(factorial(5)); //120
```
The above pattern returns the same output as the first one. But the accumulator keeps track of total as an argument without using stack memory on recursive calls.
**[⬆ Back to Top](#table-of-contents)**
412. ### How do you check an object is a promise or not
If you don't know if a value is a promise or not, wrapping the value as `Promise.resolve(value)` which returns a promise
```javascript
function isPromise(object) {
if (Promise && Promise.resolve) {
return Promise.resolve(object) == object;
} else {
throw "Promise not supported in your environment";
}
}
var i = 1;
var promise = new Promise(function (resolve, reject) {
resolve();
});
console.log(isPromise(i)); // false
console.log(isPromise(promise)); // true
```
Another way is to check for `.then()` handler type
```javascript
function isPromise(value) {
return Boolean(value && typeof value.then === "function");
}
var i = 1;
var promise = new Promise(function (resolve, reject) {
resolve();
});
console.log(isPromise(i)); // false
console.log(isPromise(promise)); // true
```
**[⬆ Back to Top](#table-of-contents)**
413. ### How to detect if a function is called as constructor
You can use `new.target` pseudo-property to detect whether a function was called as a constructor(using the new operator) or as a regular function call.
1. If a constructor or function invoked using the new operator, new.target returns a reference to the constructor or function.
2. For function calls, new.target is undefined.
```javascript
function Myfunc() {
if (new.target) {
console.log('called with new');
} else {
console.log('not called with new');
}
}
new Myfunc(); // called with new
Myfunc(); // not called with new
Myfunc.call({}); // not called with new
```
**[⬆ Back to Top](#table-of-contents)**
414. ### What are the differences between arguments object and rest parameter
There are three main differences between arguments object and rest parameters
1. The arguments object is an array-like but not an array. Whereas the rest parameters are array instances.
2. The arguments object does not support methods such as sort, map, forEach, or pop. Whereas these methods can be used in rest parameters.
3. The rest parameters are only the ones that haven’t been given a separate name, while the arguments object contains all arguments passed to the function
**[⬆ Back to Top](#table-of-contents)**
415. ### What are the differences between spread operator and rest parameter
Rest parameter collects all remaining elements into an array. Whereas Spread operator allows iterables( arrays / objects / strings ) to be expanded into single arguments/elements. i.e, Rest parameter is opposite to the spread operator.
**[⬆ Back to Top](#table-of-contents)**
416. ### What are the different kinds of generators
There are five kinds of generators,
1. **Generator function declaration:**
```javascript
function* myGenFunc() {
yield 1;
yield 2;
yield 3;
}
const genObj = myGenFunc();
```
2. **Generator function expressions:**
```javascript
const myGenFunc = function* () {
yield 1;
yield 2;
yield 3;
};
const genObj = myGenFunc();
```
3. **Generator method definitions in object literals:**
```javascript
const myObj = {
*myGeneratorMethod() {
yield 1;
yield 2;
yield 3;
},
};
const genObj = myObj.myGeneratorMethod();
```
4. **Generator method definitions in class:**
```javascript
class MyClass {
*myGeneratorMethod() {
yield 1;
yield 2;
yield 3;
}
}
const myObject = new MyClass();
const genObj = myObject.myGeneratorMethod();
```
5. **Generator as a computed property:**
```javascript
const SomeObj = {
*[Symbol.iterator]() {
yield 1;
yield 2;
yield 3;
},
};
console.log(Array.from(SomeObj)); // [ 1, 2, 3 ]
```
**[⬆ Back to Top](#table-of-contents)**
417. ### What are the built-in iterables
Below are the list of built-in iterables in javascript,
1. Arrays and TypedArrays
2. Strings: Iterate over each character or Unicode code-points
3. Maps: iterate over its key-value pairs
4. Sets: iterates over their elements
5. arguments: An array-like special variable in functions
6. DOM collection such as NodeList
**[⬆ Back to Top](#table-of-contents)**
418. ### What are the differences between for...of and for...in statements
Both for...in and for...of statements iterate over js data structures. The only difference is over what they iterate:
1. for..in iterates over all enumerable property keys of an object
2. for..of iterates over the values of an iterable object.
Let's explain this difference with an example,
```javascript
let arr = ["a", "b", "c"];
arr.newProp = "newVlue";
// key are the property keys
for (let key in arr) {
console.log(key); // 0, 1, 2 & newValue
}
// value are the property values
for (let value of arr) {
console.log(value); // a, b, c
}
```
Since for..in loop iterates over the keys of the object, the first loop logs 0, 1, 2 and newProp while iterating over the array object. The for..of loop iterates over the values of a arr data structure and logs a, b, c in the console.
**[⬆ Back to Top](#table-of-contents)**
419. ### How do you define instance and non-instance properties
The Instance properties must be defined inside of class methods. For example, name and age properties defined inside constructor as below,
```javascript
class Person {
constructor(name, age) {
this.name = name;
this.age = age;
}
}
```
But Static(class) and prototype data properties must be defined outside of the ClassBody declaration. Let's assign the age value for Person class as below,
```javascript
Person.staticAge = 30;
Person.prototype.prototypeAge = 40;
```
**[⬆ Back to Top](#table-of-contents)**
420. ### What is the difference between isNaN and Number.isNaN?
1. **isNaN**: The global function `isNaN` converts the argument to a Number and returns true if the resulting value is NaN.
2. **Number.isNaN**: This method does not convert the argument. But it returns true when the type is a Number and value is NaN.
Let's see the difference with an example,
```javascript
isNaN(‘hello’); // true
Number.isNaN('hello'); // false
```
**[⬆ Back to Top](#table-of-contents)**
421. ### How to invoke an IIFE without any extra brackets?
Immediately Invoked Function Expressions(IIFE) requires a pair of parenthesis to wrap the function which contains set of statements.
```js
(function (dt) {
console.log(dt.toLocaleTimeString());
})(new Date());
```
Since both IIFE and void operator discard the result of an expression, you can avoid the extra brackets using `void operator` for IIFE as below,
```js
void function (dt) {
console.log(dt.toLocaleTimeString());
}(new Date());
```
**[⬆ Back to Top](#table-of-contents)**
422. ### Is that possible to use expressions in switch cases?
You might have seen expressions used in switch condition but it is also possible to use for switch cases by assigning true value for the switch condition. Let's see the weather condition based on temparature as an example,
```js
const weather = (function getWeather(temp) {
switch (true) {
case temp < 0:
return "freezing";
case temp < 10:
return "cold";
case temp < 24:
return "cool";
default:
return "unknown";
}
})(10);
```
**[⬆ Back to Top](#table-of-contents)**
423. ### What is the easiest way to ignore promise errors?
The easiest and safest way to ignore promise errors is void that error. This approach is ESLint friendly too.
```js
await promise.catch((e) => void e);
```
**[⬆ Back to Top](#table-of-contents)**
424. ### How do style the console output using CSS?
You can add CSS styling to the console output using the CSS format content specifier %c. The console string message can be appended after the specifier and CSS style in another argument. Let's print the red the color text using console.log and CSS specifier as below,
```js
console.log("%cThis is a red text", "color:red");
```
It is also possible to add more styles for the content. For example, the font-size can be modified for the above text
```js
console.log(
"%cThis is a red text with bigger font",
"color:red; font-size:20px"
);
```
**[⬆ Back to Top](#table-of-contents)**
425. ### What is nullish coalescing operator (??)?
It is a logical operator that returns its right-hand side operand when its left-hand side operand is null or undefined, and otherwise returns its left-hand side operand. This can be contrasted with the logical OR (||) operator, which returns the right-hand side operand if the left operand is any falsy value, not only null or undefined.
```js
console.log(null ?? true); // true
console.log(false ?? true); // false
console.log(undefined ?? true); // true
```
**[⬆ Back to Top](#table-of-contents)**
426. ### How do you group and nest console output?
The `console.group()` can be used to group related log messages to be able to easily read the logs and use console.groupEnd()to close the group. Along with this, you can also nest groups which allows to output message in hierarchical manner.
For example, if you’re logging a user’s details:
```js
console.group("User Details");
console.log("name: Sudheer Jonna");
console.log("job: Software Developer");
// Nested Group
console.group("Address");
console.log("Street: Commonwealth");
console.log("City: Los Angeles");
console.log("State: California");
// Close nested group
console.groupEnd();
// Close outer group
console.groupEnd()
```
You can also use `console.groupCollapsed()` instead of `console.group()` if you want the groups to be collapsed by default.
**[⬆ Back to Top](#table-of-contents)**
427. ### What is the difference between dense and sparse arrays?
An array contains items at each index starting from first(0) to last(array.length - 1) is called as Dense array. Whereas if at least one item is missing at any index, the array is called as sparse.
Let's see the below two kind of arrays,
```js
const avengers = ["Ironman", "Hulk", "CaptainAmerica"];
console.log(avengers[0]); // 'Ironman'
console.log(avengers[1]); // 'Hulk'
console.log(avengers[2]); // 'CaptainAmerica'
console.log(avengers.length); // 3
const justiceLeague = ["Superman", "Aquaman", , "Batman"];
console.log(justiceLeague[0]); // 'Superman'
console.log(justiceLeague[1]); // 'Aquaman'
console.log(justiceLeague[2]); // undefined
console.log(justiceLeague[3]); // 'Batman'
console.log(justiceLeague.length); // 4
```
**[⬆ Back to Top](#table-of-contents)**
428. ### What are the different ways to create sparse arrays?
There are 4 different ways to create sparse arrays in JavaScript
1. **Array literal:** Omit a value when using the array literal
```js
const justiceLeague = ["Superman", "Aquaman", , "Batman"];
console.log(justiceLeague); // ['Superman', 'Aquaman', empty ,'Batman']
```
2. **Array() constructor:** Invoking Array(length) or new Array(length)
```js
const array = Array(3);
console.log(array); // [empty, empty ,empty]
```
3. **Delete operator:** Using delete array[index] operator on the array
```js
const justiceLeague = ["Superman", "Aquaman", "Batman"];
delete justiceLeague[1];
console.log(justiceLeague); // ['Superman', empty, ,'Batman']
```
4. **Increase length property:** Increasing length property of an array
```js
const justiceLeague = ['Superman', 'Aquaman', 'Batman'];
justiceLeague.length = 5;
console.log(justiceLeague); // ['Superman', 'Aquaman', 'Batman', empty, empty]
```
**[⬆ Back to Top](#table-of-contents)**
429. ### What is the difference between setTimeout, setImmediate and process.nextTick?
1. **Set Timeout:** setTimeout() is to schedule execution of a one-time callback after delay milliseconds.
2. **Set Immediate:** The setImmediate function is used to execute a function right after the current event loop finishes.
3. **Process NextTick:** If process.nextTick() is called in a given phase, all the callbacks passed to process.nextTick() will be resolved before the event loop continues. This will block the event loop and create I/O Starvation if process.nextTick() is called recursively.
**[⬆ Back to Top](#table-of-contents)**
430. ### How do you reverse an array without modifying original array?
The `reverse()` method reverses the order of the elements in an array but it mutates the original array. Let's take a simple example to demonistrate this case,
```javascript
const originalArray = [1, 2, 3, 4, 5];
const newArray = originalArray.reverse();
console.log(newArray); // [ 5, 4, 3, 2, 1]
console.log(originalArray); // [ 5, 4, 3, 2, 1]
```
There are few solutions that won't mutate the original array. Let's take a look.
1. **Using slice and reverse methods:**
In this case, just invoke the `slice()` method on the array to create a shallow copy followed by `reverse()` method call on the copy.
```javascript
const originalArray = [1, 2, 3, 4, 5];
const newArray = originalArray.slice().reverse(); //Slice an array gives a new copy
console.log(originalArray); // [1, 2, 3, 4, 5]
console.log(newArray); // [ 5, 4, 3, 2, 1]
```
2. **Using spread and reverse methods:**
In this case, let's use the spread syntax (...) to create a copy of the array followed by `reverse()` method call on the copy.
```javascript
const originalArray = [1, 2, 3, 4, 5];
const newArray = [...originalArray].reverse();
console.log(originalArray); // [1, 2, 3, 4, 5]
console.log(newArray); // [ 5, 4, 3, 2, 1]
```
3. **Using reduce and spread methods:**
Here execute a reducer function on an array elements and append the accumulated array on right side using spread syntax
```javascript
const originalArray = [1, 2, 3, 4, 5];
const newArray = originalArray.reduce((accumulator, value) => {
return [value, ...accumulator];
}, []);
console.log(originalArray); // [1, 2, 3, 4, 5]
console.log(newArray); // [ 5, 4, 3, 2, 1]
```
4. **Using reduceRight and spread methods:**
Here execute a right reducer function(i.e. opposite direction of reduce method) on an array elements and append the accumulated array on left side using spread syntax
```javascript
const originalArray = [1, 2, 3, 4, 5];
const newArray = originalArray.reduceRight((accumulator, value) => {
return [...accumulator, value];
}, []);
console.log(originalArray); // [1, 2, 3, 4, 5]
console.log(newArray); // [ 5, 4, 3, 2, 1]
```
5. **Using reduceRight and push methods:**
Here execute a right reducer function(i.e. opposite direction of reduce method) on an array elements and push the iterated value to the accumulator
```javascript
const originalArray = [1, 2, 3, 4, 5];
const newArray = originalArray.reduceRight((accumulator, value) => {
accumulator.push(value);
return accumulator;
}, []);
console.log(originalArray); // [1, 2, 3, 4, 5]
console.log(newArray); // [ 5, 4, 3, 2, 1]
```
**[⬆ Back to Top](#table-of-contents)**
431. ### How do you create custom HTML element?
The creation of custom HTML elements involves two main steps,
1. **Define your custom HTML element:** First you need to define some custom class by extending HTMLElement class.
After that define your component properties (styles,text etc) using `connectedCallback` method.
**Note:** The browser exposes a function called `customElements.define` inorder to reuse the element.
```javascript
class CustomElement extends HTMLElement {
connectedCallback() {
this.innerHTML = "This is a custom element";
}
}
customElements.define("custom-element", CustomElement);
```
2. **Use custome element just like other HTML element:** Declare your custom element as a HTML tag.
```javascript
<body>
<custom-element>
</body>
```
**[⬆ Back to Top](#table-of-contents)**
432. ### What is global execution context?
The global execution context is the default or first execution context that is created by the JavaScript engine before any code is executed(i.e, when the file first loads in the browser). All the global code that is not inside a function or object will be executed inside this global execution context. Since JS engine is single threaded there will be only one global environment and there will be only one global execution context.
For example, the below code other than code inside any function or object is executed inside the global execution context.
```javascript
var x = 10;
function A() {
console.log("Start function A");
function B() {
console.log("In function B");
}
B();
}
A();
console.log("GlobalContext");
```
**[⬆ Back to Top](#table-of-contents)**
433. ### What is function execution context?
Whenever a function is invoked, the JavaScript engine creates a different type of Execution Context known as a Function Execution Context (FEC) within the Global Execution Context (GEC) to evaluate and execute the code within that function.
**[⬆ Back to Top](#table-of-contents)**
434. ### What is debouncing?
Debouncing is a programming pattern that allows delaying execution of some piece of code until a specified time to avoid unnecessary _CPU cycles, API calls and improve performance_. The debounce function make sure that your code is only triggered once per user input. The common usecases are Search box suggestions, text-field auto-saves, and eliminating double-button clicks.
Let's say you want to show suggestions for a search query, but only after a visitor has finished typing it. So here you write a debounce function where the user keeps writing the characters with in 500ms then previous timer cleared out using `clearTimeout` and reschedule API call/DB query for a new time—300 ms in the future.
```js
function debounce(func, timeout = 500) {
let timer;
return (...args) => {
clearTimeout(timer);
timer = setTimeout(() => {
func.apply(this, args);
}, timeout);
};
}
function fetchResults() {
console.log("Fetching input suggestions");
}
const processChange = debounce(() => fetchResults());
```
The _debounce()_ function can be used on input, button and window events
**Input:**
```html
<input type="text" onkeyup="processChange()" />
```
**Button:**
```html
<button onclick="processChange()">Click me</button>
```
**Windows event:**
```html
window.addEventListener("scroll", processChange);
```
**[⬆ Back to Top](#table-of-contents)**
435. ### What is throttling?
Throttling is a technique used to limit the execution of an event handler function, even when this event triggers continuously due to user actions. The common use cases are browser resizing, window scrolling etc.
The below example creates a throttle function to reduce the number of events for each pixel change and trigger scroll event for each 100ms except for the first event.
```js
const throttle = (func, limit) => {
let inThrottle;
return (...args) => {
if (!inThrottle) {
func.apply(this, args);
inThrottle = true;
setTimeout(() => (inThrottle = false), limit);
}
};
};
window.addEventListener("scroll", () => {
throttle(handleScrollAnimation, 100);
});
```
**[⬆ Back to Top](#table-of-contents)**
436. ### What is optional chaining?
According to MDN official docs, the optional chaining operator (?.) permits reading the value of a property located deep within a chain of connected objects without having to expressly validate that each reference in the chain is valid.
The ?. operator is like the . chaining operator, except that instead of causing an error if a reference is nullish (null or undefined), the expression short-circuits with a return value of undefined. When used with function calls, it returns undefined if the given function does not exist.
```js
const adventurer = {
name: 'Alice',
cat: {
name: 'Dinah'
}
};
const dogName = adventurer.dog?.name;
console.log(dogName);
// expected output: undefined
console.log(adventurer.someNonExistentMethod?.());
// expected output: undefined
```
**[⬆ Back to Top](#table-of-contents)**
437. ### What is an environment record?
According to ECMAScript specification 262 (9.1):
>[Environment Record](https://262.ecma-international.org/12.0/#sec-environment-records) is a specification type used to define the association of Identifiers to specific variables and functions, based upon the lexical nesting structure of ECMAScript code.
Usually an Environment Record is associated with some specific syntactic structure of ECMAScript code such as a FunctionDeclaration, a BlockStatement, or a Catch clause of a TryStatement.
Each time such code is evaluated, a new Environment Record is created to record the identifier bindings that are created by that code.
**[⬆ Back to Top](#table-of-contents)**
438. ### How to verify if a variable is an array?
It is possible to check if a variable is an array instance using 3 different ways,
1. Array.isArray() method:
The `Array.isArray(value)` utility function is used to determine whether value is an array or not. This function returns a true boolean value if the variable is an array and a false value if it is not.
```javascript
const numbers = [1, 2, 3];
const user = { name: 'John' };
Array.isArray(numbers); // true
Array.isArray(user); //false
```
2. instanceof operator:
The instanceof operator is used to check the type of an array at run time. It returns true if the type of a variable is an Array other false for other type.
```javascript
const numbers = [1, 2, 3];
const user = { name: 'John' };
console.log(numbers instanceof Array); // true
console.log(user instanceof Array); // false
```
3. Checking constructor type:
The constructor property of the variable is used to determine whether the variable Array type or not.
```javascript
const numbers = [1, 2, 3];
const user = { name: 'John' };
console.log(numbers.constructor === Array); // true
console.log(user.constructor === Array); // false
```
**[⬆ Back to Top](#table-of-contents)**
439. ### What is pass by value and pass by reference?
Pass-by-value creates a new space in memory and makes a copy of a value. Primitives such as string, number, boolean etc will actually create a new copy. Hence, updating one value doesn't impact the other value. i.e, The values are independent of each other.
```javascript
let a = 5;
let b = a;
b++;
console.log(a, b); //5, 6
```
In the above code snippet, the value of `a` is assigned to `b` and the variable `b` has been incremented. Since there is a new space created for variable `b`, any update on this variable doesn't impact the variable `a`.
Pass by reference doesn't create a new space in memory but the new variable adopts a memory address of an initial variable. Non-primitives such as objects, arrays and functions gets the reference of the initiable variable. i.e, updating one value will impact the other variable.
```javascript
let user1 = {
name: 'John',
age: 27
};
let user2 = user1;
user2.age = 30;
console.log(user1.age, user2.age); // 30, 30
```
In the above code snippet, updating the `age` property of one object will impact the other property due to the same reference.
**[⬆ Back to Top](#table-of-contents)**
440. ### What are the differences between primitives and non-primitives?
JavaScript language has both primitives and non-primitives but there are few differences between them as below,
| Primitives | Non-primitives |
|---- | ---------
| These types are predefined | Created by developer |
| These are immutable | Mutable |
| Compare by value | Compare by reference |
| Stored in Stack | Stored in heap |
| Contain certain value | Can contain NULL too |
**[⬆ Back to Top](#table-of-contents)**
443. ### How do you create your own bind method using either call or apply method?
The custom bind function needs to be created on Function prototype inorder to use it as other builtin functions. This custom function should return a function similar to original bind method and the implementation of inner function needs to use apply method call.
The function which is going to bind using custom `myOwnBind` method act as the attached function(`boundTargetFunction`) and argument as the object for `apply` method call.
```js
Function.prototype.myOwnBind = function(whoIsCallingMe) {
if (typeof this !== "function") {
throw new Error(this + "cannot be bound as it's not callable");
}
const boundTargetFunction = this;
return function() {
boundTargetFunction.apply(whoIsCallingMe, arguments);
}
}
```
**[⬆ Back to Top](#table-of-contents)**
444. ### What are the differences between pure and impure functions?
Some of the major differences between pure and impure function are as below,
| Pure function | Impure function |
| -------- | ------------------------------------------------------- |
| It has no side effects | It causes side effects |
| It is always return the same result | It returns different result on each call |
| Easy to read and debug | Difficult to read and debug because they are affected by extenal code
**[⬆ Back to Top](#table-of-contents)**
445. ### What is referential transparency?
An expression in javascript can be replaced by its value without affecting the behaviour of the program is called referential transparency. Pure functions are referentially transparent.
```javascript
const add = (x,y) => x + y;
const multiplyBy2 = (x) => x * 2;
//Now add (2, 3) can be replaced by 5.
multiplyBy2(add(2, 3));
```
**[⬆ Back to Top](#table-of-contents)**
446. ### What are the possible side-effects in javascript?
A side effect is the modification of state through the invocation of a function or expression. These side effects makes our function impure by default. Below are some side effects which makes function impure,
1. Making an HTTP request. Asynchronous functions such as fetch and promise are impure.
2. DOM manipulations
3. Mutating the input data
4. Printing to a screen or console: For example, console.log() and alert()
5. Fetching the current time
6. Math.random() calls: Modifies the internal state of Math object
**[⬆ Back to Top](#table-of-contents)**
447. ### What are compose and pipe functions?
The "compose" and "pipe" are two techniques commonly used in functional programming to simplify complex operations and make code more readable. They are not native in JavaScript and higher order functions. the `compose()` applies right to left any number of functions to the output of the previous function.
**[⬆ Back to Top](#table-of-contents)**
448. ### What is module pattern?
Module pattern is a designed pattern used to wrap a set of variables and functions together in a single scope returned as an object. JavaScript doesn't have access specifiers similar to other languages(Java, Pythong etc) to provide private scope. It uses IIFE (Immediately invoked function expression) to allow for private scopes. i.e, a closure that protect variables and methods.
The module pattern look like below,
```javascript
(function() {
// Private variables or functions goes here.
return {
// Return public variables or functions here.
}
})();
```
Let's see an example of module pattern for an employee with private and public access,
```javascript
const createEmployee = (function () {
// Private
const name = "John";
const department = "Sales";
const getEmployeeName = () => name;
const getDepartmentName = () => department;
// Public
return {
name,
department,
getName: () => getEmployeeName(),
getDepartment: () => getDepartmentName(),
};
})();
console.log(createEmployee.name);
console.log(createEmployee.department);
console.log(createEmployee.getName());
console.log(createEmployee.getDepartment());
```
**Note:** It mimic the concepts of classes with private variables and methods.
**[⬆ Back to Top](#table-of-contents)**
449. ### What is Function Composition?
It is an approach where the result of one function is passed on to the next function, which is passed to another until the final function is executed for the final result.
```javascript
//example
const double = x => x * 2
const square = x => x * x
var output1 = double(2);
var output2 = square(output1);
console.log(output2);
var output_final = square(double(2));
console.log(output_final);
```
**[⬆ Back to Top](#table-of-contents)**
450. ### How to use await outside of async function prior to ES2022?
Prior to ES2022, if you attempted to use an await outside of an async function resulted in a SyntaxError.
```javascript
await Promise.resolve(console.log('Hello await')); // SyntaxError: await is only valid in async function
```
But you can fix this issue with an alternative IIFE (Immediately Invoked Function Expression) to get access to the feature.
```javascript
(async function() {
await Promise.resolve(console.log('Hello await')); // Hello await
}());
```
In ES2022, you can write top-level await without writing any hacks.
```javascript
await Promise.resolve(console.log('Hello await')); //Hello await
```
**[⬆ Back to Top](#table-of-contents)**
### Coding Exercise
#### 1. What is the output of below code
```javascript
var car = new Vehicle("Honda", "white", "2010", "UK");
console.log(car);
function Vehicle(model, color, year, country) {
this.model = model;
this.color = color;
this.year = year;
this.country = country;
}
```
- 1: Undefined
- 2: ReferenceError
- 3: null
- 4: {model: "Honda", color: "white", year: "2010", country: "UK"}
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
The function declarations are hoisted similar to any variables. So the placement for `Vehicle` function declaration doesn't make any difference.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 2. What is the output of below code
```javascript
function foo() {
let x = (y = 0);
x++;
y++;
return x;
}
console.log(foo(), typeof x, typeof y);
```
- 1: 1, undefined and undefined
- 2: ReferenceError: X is not defined
- 3: 1, undefined and number
- 4: 1, number and number
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
Of course the return value of `foo()` is 1 due to the increment operator. But the statement `let x = y = 0` declares a local variable x. Whereas y declared as a global variable accidentally. This statement is equivalent to,
```javascript
let x;
window.y = 0;
x = window.y;
```
Since the block scoped variable x is undefined outside of the function, the type will be undefined too. Whereas the global variable `y` is available outside the function, the value is 0 and type is number.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 3. What is the output of below code
```javascript
function main() {
console.log("A");
setTimeout(function print() {
console.log("B");
}, 0);
console.log("C");
}
main();
```
- 1: A, B and C
- 2: B, A and C
- 3: A and C
- 4: A, C and B
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
The statements order is based on the event loop mechanism. The order of statements follows the below order,
1. At first, the main function is pushed to the stack.
2. Then the browser pushes the first statement of the main function( i.e, A's console.log) to the stack, executing and popping out immediately.
3. But `setTimeout` statement moved to Browser API to apply the delay for callback.
4. In the meantime, C's console.log added to stack, executed and popped out.
5. The callback of `setTimeout` moved from Browser API to message queue.
6. The `main` function popped out from stack because there are no statements to execute
7. The callback moved from message queue to the stack since the stack is empty.
8. The console.log for B is added to the stack and display on the console.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 4. What is the output of below equality check
```javascript
console.log(0.1 + 0.2 === 0.3);
```
- 1: false
- 2: true
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
This is due to the float point math problem. Since the floating point numbers are encoded in binary format, the addition operations on them lead to rounding errors. Hence, the comparison of floating points doesn't give expected results.
You can find more details about the explanation here [0.30000000000000004.com/](https://0.30000000000000004.com/)
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 5. What is the output of below code
```javascript
var y = 1;
if (function f() {}) {
y += typeof f;
}
console.log(y);
```
- 1: 1function
- 2: 1object
- 3: ReferenceError
- 4: 1undefined
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
The main points in the above code snippets are,
1. You can see function expression instead function declaration inside if statement. So it always returns true.
2. Since it is not declared(or assigned) anywhere, f is undefined and typeof f is undefined too.
In other words, it is same as
```javascript
var y = 1;
if ("foo") {
y += typeof f;
}
console.log(y);
```
**Note:** It returns 1object for MS Edge browser
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 6. What is the output of below code
```javascript
function foo() {
return;
{
message: "Hello World";
}
}
console.log(foo());
```
- 1: Hello World
- 2: Object {message: "Hello World"}
- 3: Undefined
- 4: SyntaxError
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
This is a semicolon issue. Normally semicolons are optional in JavaScript. So if there are any statements(in this case, return) missing semicolon, it is automatically inserted immediately. Hence, the function returned as undefined.
Whereas if the opening curly brace is along with the return keyword then the function is going to be returned as expected.
```javascript
function foo() {
return {
message: "Hello World",
};
}
console.log(foo()); // {message: "Hello World"}
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 7. What is the output of below code
```javascript
var myChars = ["a", "b", "c", "d"];
delete myChars[0];
console.log(myChars);
console.log(myChars[0]);
console.log(myChars.length);
```
- 1: [empty, 'b', 'c', 'd'], empty, 3
- 2: [null, 'b', 'c', 'd'], empty, 3
- 3: [empty, 'b', 'c', 'd'], undefined, 4
- 4: [null, 'b', 'c', 'd'], undefined, 4
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
The `delete` operator will delete the object property but it will not reindex the array or change its length. So the number or elements or length of the array won't be changed.
If you try to print myChars then you can observe that it doesn't set an undefined value, rather the property is removed from the array. The newer versions of Chrome use `empty` instead of `undefined` to make the difference a bit clearer.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 8. What is the output of below code in latest Chrome
```javascript
var array1 = new Array(3);
console.log(array1);
var array2 = [];
array2[2] = 100;
console.log(array2);
var array3 = [, , ,];
console.log(array3);
```
- 1: [undefined × 3], [undefined × 2, 100], [undefined × 3]
- 2: [empty × 3], [empty × 2, 100], [empty × 3]
- 3: [null × 3], [null × 2, 100], [null × 3]
- 4: [], [100], []
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
The latest chrome versions display `sparse array`(they are filled with holes) using this empty x n notation. Whereas the older versions have undefined x n notation.
**Note:** The latest version of FF displays `n empty slots` notation.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 9. What is the output of below code
```javascript
const obj = {
prop1: function () {
return 0;
},
prop2() {
return 1;
},
["prop" + 3]() {
return 2;
},
};
console.log(obj.prop1());
console.log(obj.prop2());
console.log(obj.prop3());
```
- 1: 0, 1, 2
- 2: 0, { return 1 }, 2
- 3: 0, { return 1 }, { return 2 }
- 4: 0, 1, undefined
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
ES6 provides method definitions and property shorthands for objects. So both prop2 and prop3 are treated as regular function values.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 10. What is the output of below code
```javascript
console.log(1 < 2 < 3);
console.log(3 > 2 > 1);
```
- 1: true, true
- 2: true, false
- 3: SyntaxError, SyntaxError,
- 4: false, false
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
The important point is that if the statement contains the same operators(e.g, < or >) then it can be evaluated from left to right.
The first statement follows the below order,
1. console.log(1 < 2 < 3);
2. console.log(true < 3);
3. console.log(1 < 3); // True converted as `1` during comparison
4. True
Whereas the second statement follows the below order,
1. console.log(3 > 2 > 1);
2. console.log(true > 1);
3. console.log(1 > 1); // False converted as `0` during comparison
4. False
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 11. What is the output of below code in non-strict mode
```javascript
function printNumbers(first, second, first) {
console.log(first, second, first);
}
printNumbers(1, 2, 3);
```
- 1: 1, 2, 3
- 2: 3, 2, 3
- 3: SyntaxError: Duplicate parameter name not allowed in this context
- 4: 1, 2, 1
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
In non-strict mode, the regular JavaScript functions allow duplicate named parameters. The above code snippet has duplicate parameters on 1st and 3rd parameters.
The value of the first parameter is mapped to the third argument which is passed to the function. Hence, the 3rd argument overrides the first parameter.
**Note:** In strict mode, duplicate parameters will throw a Syntax Error.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 12. What is the output of below code
```javascript
const printNumbersArrow = (first, second, first) => {
console.log(first, second, first);
};
printNumbersArrow(1, 2, 3);
```
- 1: 1, 2, 3
- 2: 3, 2, 3
- 3: SyntaxError: Duplicate parameter name not allowed in this context
- 4: 1, 2, 1
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
Unlike regular functions, the arrow functions doesn't not allow duplicate parameters in either strict or non-strict mode. So you can see `SyntaxError` in the console.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 13. What is the output of below code
```javascript
const arrowFunc = () => arguments.length;
console.log(arrowFunc(1, 2, 3));
```
- 1: ReferenceError: arguments is not defined
- 2: 3
- 3: undefined
- 4: null
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
Arrow functions do not have an `arguments, super, this, or new.target` bindings. So any reference to `arguments` variable tries to resolve to a binding in a lexically enclosing environment. In this case, the arguments variable is not defined outside of the arrow function. Hence, you will receive a reference error.
Where as the normal function provides the number of arguments passed to the function
```javascript
const func = function () {
return arguments.length;
};
console.log(func(1, 2, 3));
```
But If you still want to use an arrow function then rest operator on arguments provides the expected arguments
```javascript
const arrowFunc = (...args) => args.length;
console.log(arrowFunc(1, 2, 3));
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 14. What is the output of below code
```javascript
console.log(String.prototype.trimLeft.name === "trimLeft");
console.log(String.prototype.trimLeft.name === "trimStart");
```
- 1: True, False
- 2: False, True
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
In order to be consistent with functions like `String.prototype.padStart`, the standard method name for trimming the whitespaces is considered as `trimStart`. Due to web web compatibility reasons, the old method name 'trimLeft' still acts as an alias for 'trimStart'. Hence, the prototype for 'trimLeft' is always 'trimStart'
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 15. What is the output of below code
```javascript
console.log(Math.max());
```
- 1: undefined
- 2: Infinity
- 3: 0
- 4: -Infinity
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
-Infinity is the initial comparant because almost every other value is bigger. So when no arguments are provided, -Infinity is going to be returned.
**Note:** Zero number of arguments is a valid case.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 16. What is the output of below code
```javascript
console.log(10 == [10]);
console.log(10 == [[[[[[[10]]]]]]]);
```
- 1: True, True
- 2: True, False
- 3: False, False
- 4: False, True
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
As per the comparison algorithm in the ECMAScript specification(ECMA-262), the above expression converted into JS as below
```javascript
10 === Number([10].valueOf().toString()); // 10
```
So it doesn't matter about number brackets([]) around the number, it is always converted to a number in the expression.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 17. What is the output of below code
```javascript
console.log(10 + "10");
console.log(10 - "10");
```
- 1: 20, 0
- 2: 1010, 0
- 3: 1010, 10-10
- 4: NaN, NaN
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
The concatenation operator(+) is applicable for both number and string types. So if any operand is string type then both operands concatenated as strings. Whereas subtract(-) operator tries to convert the operands as number type.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 18. What is the output of below code
```javascript
console.log([0] == false);
if ([0]) {
console.log("I'm True");
} else {
console.log("I'm False");
}
```
- 1: True, I'm True
- 2: True, I'm False
- 3: False, I'm True
- 4: False, I'm False
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
In comparison operators, the expression `[0]` converted to Number([0].valueOf().toString()) which is resolved to false. Whereas `[0]` just becomes a truthy value without any conversion because there is no comparison operator.
</p>
</details>
#### 19. What is the output of below code
```javascript
console.log([1, 2] + [3, 4]);
```
- 1: [1,2,3,4]
- 2: [1,2][3,4]
- 3: SyntaxError
- 4: 1,23,4
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
The + operator is not meant or defined for arrays. So it converts arrays into strings and concatenates them.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 20. What is the output of below code
```javascript
const numbers = new Set([1, 1, 2, 3, 4]);
console.log(numbers);
const browser = new Set("Firefox");
console.log(browser);
```
- 1: {1, 2, 3, 4}, {"F", "i", "r", "e", "f", "o", "x"}
- 2: {1, 2, 3, 4}, {"F", "i", "r", "e", "o", "x"}
- 3: [1, 2, 3, 4], ["F", "i", "r", "e", "o", "x"]
- 4: {1, 1, 2, 3, 4}, {"F", "i", "r", "e", "f", "o", "x"}
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
Since `Set` object is a collection of unique values, it won't allow duplicate values in the collection. At the same time, it is case sensitive data structure.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 21. What is the output of below code
```javascript
console.log(NaN === NaN);
```
- 1: True
- 2: False
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
JavaScript follows IEEE 754 spec standards. As per this spec, NaNs are never equal for floating-point numbers.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 22. What is the output of below code
```javascript
let numbers = [1, 2, 3, 4, NaN];
console.log(numbers.indexOf(NaN));
```
- 1: 4
- 2: NaN
- 3: SyntaxError
- 4: -1
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
The `indexOf` uses strict equality operator(===) internally and `NaN === NaN` evaluates to false. Since indexOf won't be able to find NaN inside an array, it returns -1 always.
But you can use `Array.prototype.findIndex` method to find out the index of NaN in an array or You can use `Array.prototype.includes` to check if NaN is present in an array or not.
```javascript
let numbers = [1, 2, 3, 4, NaN];
console.log(numbers.findIndex(Number.isNaN)); // 4
console.log(numbers.includes(NaN)); // true
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 23. What is the output of below code
```javascript
let [a, ...b,] = [1, 2, 3, 4, 5];
console.log(a, b);
```
- 1: 1, [2, 3, 4, 5]
- 2: 1, {2, 3, 4, 5}
- 3: SyntaxError
- 4: 1, [2, 3, 4]
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
When using rest parameters, trailing commas are not allowed and will throw a SyntaxError.
If you remove the trailing comma then it displays 1st answer
```javascript
let [a, ...b] = [1, 2, 3, 4, 5];
console.log(a, b); // 1, [2, 3, 4, 5]
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 25. What is the output of below code
```javascript
async function func() {
return 10;
}
console.log(func());
```
- 1: Promise {\<fulfilled\>: 10}
- 2: 10
- 3: SyntaxError
- 4: Promise {\<rejected\>: 10}
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
Async functions always return a promise. But even if the return value of an async function is not explicitly a promise, it will be implicitly wrapped in a promise. The above async function is equivalent to below expression,
```javascript
function func() {
return Promise.resolve(10);
}
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 26. What is the output of below code
```javascript
async function func() {
await 10;
}
console.log(func());
```
- 1: Promise {\<fulfilled\>: 10}
- 2: 10
- 3: SyntaxError
- 4: Promise {\<resolved\>: undefined}
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
The await expression returns value 10 with promise resolution and the code after each await expression can be treated as existing in a `.then` callback. In this case, there is no return expression at the end of the function. Hence, the default return value of `undefined` is returned as the resolution of the promise. The above async function is equivalent to below expression,
```javascript
function func() {
return Promise.resolve(10).then(() => undefined);
}
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 27. What is the output of below code
```javascript
function delay() {
return new Promise(resolve => setTimeout(resolve, 2000));
}
async function delayedLog(item) {
await delay();
console.log(item);
}
async function processArray(array) {
array.forEach(item => {
await delayedLog(item);
})
}
processArray([1, 2, 3, 4]);
```
- 1: SyntaxError
- 2: 1, 2, 3, 4
- 3: 4, 4, 4, 4
- 4: 4, 3, 2, 1
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
Even though “processArray” is an async function, the anonymous function that we use for `forEach` is synchronous. If you use await inside a synchronous function then it throws a syntax error.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 28. What is the output of below code
```javascript
function delay() {
return new Promise((resolve) => setTimeout(resolve, 2000));
}
async function delayedLog(item) {
await delay();
console.log(item);
}
async function process(array) {
array.forEach(async (item) => {
await delayedLog(item);
});
console.log("Process completed!");
}
process([1, 2, 3, 5]);
```
- 1: 1 2 3 5 and Process completed!
- 2: 5 5 5 5 and Process completed!
- 3: Process completed! and 5 5 5 5
- 4: Process completed! and 1 2 3 5
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
The forEach method will not wait until all items are finished but it just runs the tasks and goes next. Hence, the last statement is displayed first followed by a sequence of promise resolutions.
But you control the array sequence using for..of loop,
```javascript
async function processArray(array) {
for (const item of array) {
await delayedLog(item);
}
console.log("Process completed!");
}
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 29. What is the output of below code
```javascript
var set = new Set();
set.add("+0").add("-0").add(NaN).add(undefined).add(NaN);
console.log(set);
```
- 1: Set(4) {"+0", "-0", NaN, undefined}
- 2: Set(3) {"+0", NaN, undefined}
- 3: Set(5) {"+0", "-0", NaN, undefined, NaN}
- 4: Set(4) {"+0", NaN, undefined, NaN}
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
Set has few exceptions from equality check,
1. All NaN values are equal
2. Both +0 and -0 considered as different values
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 30. What is the output of below code
```javascript
const sym1 = Symbol("one");
const sym2 = Symbol("one");
const sym3 = Symbol.for("two");
const sym4 = Symbol.for("two");
console.log(sym1 === sym2, sym3 === sym4);
```
- 1: true, true
- 2: true, false
- 3: false, true
- 4: false, false
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
Symbol follows below conventions,
1. Every symbol value returned from Symbol() is unique irrespective of the optional string.
2. `Symbol.for()` function creates a symbol in a global symbol registry list. But it doesn't necessarily create a new symbol on every call, it checks first if a symbol with the given key is already present in the registry and returns the symbol if it is found. Otherwise a new symbol created in the registry.
**Note:** The symbol description is just useful for debugging purposes.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 31. What is the output of below code
```javascript
const sym1 = new Symbol("one");
console.log(sym1);
```
- 1: SyntaxError
- 2: one
- 3: Symbol('one')
- 4: Symbol
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
`Symbol` is a just a standard function and not an object constructor(unlike other primitives new Boolean, new String and new Number). So if you try to call it with the new operator will result in a TypeError
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 32. What is the output of below code
```javascript
let myNumber = 100;
let myString = "100";
if (!typeof myNumber === "string") {
console.log("It is not a string!");
} else {
console.log("It is a string!");
}
if (!typeof myString === "number") {
console.log("It is not a number!");
} else {
console.log("It is a number!");
}
```
- 1: SyntaxError
- 2: It is not a string!, It is not a number!
- 3: It is not a string!, It is a number!
- 4: It is a string!, It is a number!
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
The return value of `typeof myNumber` or `typeof myString` is always a truthy value (either "number" or "string"). The ! operator operates on either `typeof myNumber` or `typeof myString`, converting them to boolean values. Since the value of both `!typeof myNumber` and `!typeof myString` is false, the if condition fails, and control goes to else block.
To make the ! operator operate on the equality expression, one needs to add parentheses:
```
if (!(typeof myNumber === "string"))
```
Or simply use the inequality operator:
```
if (typeof myNumber !== "string")
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 33. What is the output of below code
```javascript
console.log(
JSON.stringify({ myArray: ["one", undefined, function () {}, Symbol("")] })
);
console.log(
JSON.stringify({ [Symbol.for("one")]: "one" }, [Symbol.for("one")])
);
```
- 1: {"myArray":['one', undefined, {}, Symbol]}, {}
- 2: {"myArray":['one', null,null,null]}, {}
- 3: {"myArray":['one', null,null,null]}, "{ [Symbol.for('one')]: 'one' }, [Symbol.for('one')]"
- 4: {"myArray":['one', undefined, function(){}, Symbol('')]}, {}
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
The symbols has below constraints,
1. The undefined, Functions, and Symbols are not valid JSON values. So those values are either omitted (in an object) or changed to null (in an array). Hence, it returns null values for the value array.
2. All Symbol-keyed properties will be completely ignored. Hence it returns an empty object({}).
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 34. What is the output of below code
```javascript
class A {
constructor() {
console.log(new.target.name);
}
}
class B extends A {
constructor() {
super();
}
}
new A();
new B();
```
- 1: A, A
- 2: A, B
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
Using constructors, `new.target` refers to the constructor (points to the class definition of class which is initialized) that was directly invoked by new. This also applies to the case if the constructor is in a parent class and was delegated from a child constructor.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 35. What is the output of below code
```javascript
const [x, ...y, z] = [1, 2, 3, 4];
console.log(x, y, z);
```
- 1: 1, [2, 3], 4
- 2: 1, [2, 3, 4], undefined
- 3: 1, [2], 3
- 4: SyntaxError
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
It throws a syntax error because the rest element should not have a trailing comma. You should always consider using a rest operator as the last element.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 36. What is the output of below code
```javascript
const { a: x = 10, b: y = 20 } = { a: 30 };
console.log(x);
console.log(y);
```
- 1: 30, 20
- 2: 10, 20
- 3: 10, undefined
- 4: 30, undefined
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
The object property follows below rules,
1. The object properties can be retrieved and assigned to a variable with a different name
2. The property assigned a default value when the retrieved value is `undefined`
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 37. What is the output of below code
```javascript
function area({ length = 10, width = 20 }) {
console.log(length * width);
}
area();
```
- 1: 200
- 2: Error
- 3: undefined
- 4: 0
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
If you leave out the right-hand side assignment for the destructuring object, the function will look for at least one argument to be supplied when invoked. Otherwise you will receive an error `Error: Cannot read property 'length' of undefined` as mentioned above.
You can avoid the error with either of the below changes,
1. **Pass at least an empty object:**
```javascript
function area({ length = 10, width = 20 }) {
console.log(length * width);
}
area({});
```
2. **Assign default empty object:**
```javascript
function area({ length = 10, width = 20 } = {}) {
console.log(length * width);
}
area();
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 38. What is the output of below code
```javascript
const props = [
{ id: 1, name: "John" },
{ id: 2, name: "Jack" },
{ id: 3, name: "Tom" },
];
const [, , { name }] = props;
console.log(name);
```
- 1: Tom
- 2: Error
- 3: undefined
- 4: John
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
It is possible to combine Array and Object destructuring. In this case, the third element in the array props accessed first followed by name property in the object.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 39. What is the output of below code
```javascript
function checkType(num = 1) {
console.log(typeof num);
}
checkType();
checkType(undefined);
checkType("");
checkType(null);
```
- 1: number, undefined, string, object
- 2: undefined, undefined, string, object
- 3: number, number, string, object
- 4: number, number, number, number
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
If the function argument is set implicitly(not passing argument) or explicitly to undefined, the value of the argument is the default parameter. Whereas for other falsy values('' or null), the value of the argument is passed as a parameter.
Hence, the result of function calls categorized as below,
1. The first two function calls logs number type since the type of default value is number
2. The type of '' and null values are string and object type respectively.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 40. What is the output of below code
```javascript
function add(item, items = []) {
items.push(item);
return items;
}
console.log(add("Orange"));
console.log(add("Apple"));
```
- 1: ['Orange'], ['Orange', 'Apple']
- 2: ['Orange'], ['Apple']
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
Since the default argument is evaluated at call time, a new object is created each time the function is called. So in this case, the new array is created and an element pushed to the default empty array.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 41. What is the output of below code
```javascript
function greet(greeting, name, message = greeting + " " + name) {
console.log([greeting, name, message]);
}
greet("Hello", "John");
greet("Hello", "John", "Good morning!");
```
- 1: SyntaxError
- 2: ['Hello', 'John', 'Hello John'], ['Hello', 'John', 'Good morning!']
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
Since parameters defined earlier are available to later default parameters, this code snippet doesn't throw any error.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 42. What is the output of below code
```javascript
function outer(f = inner()) {
function inner() {
return "Inner";
}
}
outer();
```
- 1: ReferenceError
- 2: Inner
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
The functions and variables declared in the function body cannot be referred from default value parameter initializers. If you still try to access, it throws a run-time ReferenceError(i.e, `inner` is not defined).
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 43. What is the output of below code
```javascript
function myFun(x, y, ...manyMoreArgs) {
console.log(manyMoreArgs);
}
myFun(1, 2, 3, 4, 5);
myFun(1, 2);
```
- 1: [3, 4, 5], undefined
- 2: SyntaxError
- 3: [3, 4, 5], []
- 4: [3, 4, 5], [undefined]
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
The rest parameter is used to hold the remaining parameters of a function and it becomes an empty array if the argument is not provided.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 44. What is the output of below code
```javascript
const obj = { key: "value" };
const array = [...obj];
console.log(array);
```
- 1: ['key', 'value']
- 2: TypeError
- 3: []
- 4: ['key']
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
Spread syntax can be applied only to iterable objects. By default, Objects are not iterable, but they become iterable when used in an Array, or with iterating functions such as `map(), reduce(), and assign()`. If you still try to do it, it still throws `TypeError: obj is not iterable`.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 45. What is the output of below code
```javascript
function* myGenFunc() {
yield 1;
yield 2;
yield 3;
}
var myGenObj = new myGenFunc();
console.log(myGenObj.next().value);
```
- 1: 1
- 2: undefined
- 3: SyntaxError
- 4: TypeError
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
Generators are not constructible type. But if you still proceed to do, there will be an error saying "TypeError: myGenFunc is not a constructor"
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 46. What is the output of below code
```javascript
function* yieldAndReturn() {
yield 1;
return 2;
yield 3;
}
var myGenObj = yieldAndReturn();
console.log(myGenObj.next());
console.log(myGenObj.next());
console.log(myGenObj.next());
```
- 1: { value: 1, done: false }, { value: 2, done: true }, { value: undefined, done: true }
- 2: { value: 1, done: false }, { value: 2, done: false }, { value: undefined, done: true }
- 3: { value: 1, done: false }, { value: 2, done: true }, { value: 3, done: true }
- 4: { value: 1, done: false }, { value: 2, done: false }, { value: 3, done: true }
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
A return statement in a generator function will make the generator finish. If a value is returned, it will be set as the value property of the object and done property to true. When a generator is finished, subsequent next() calls return an object of this form: `{value: undefined, done: true}`.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 47. What is the output of below code
```javascript
const myGenerator = (function* () {
yield 1;
yield 2;
yield 3;
})();
for (const value of myGenerator) {
console.log(value);
break;
}
for (const value of myGenerator) {
console.log(value);
}
```
- 1: 1,2,3 and 1,2,3
- 2: 1,2,3 and 4,5,6
- 3: 1 and 1
- 4: 1
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
The generator should not be re-used once the iterator is closed. i.e, Upon exiting a loop(on completion or using break & return), the generator is closed and trying to iterate over it again does not yield any more results. Hence, the second loop doesn't print any value.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 48. What is the output of below code
```javascript
const num = 0o38;
console.log(num);
```
- 1: SyntaxError
- 2: 38
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
If you use an invalid number(outside of 0-7 range) in the octal literal, JavaScript will throw a SyntaxError. In ES5, it treats the octal literal as a decimal number.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 49. What is the output of below code
```javascript
const squareObj = new Square(10);
console.log(squareObj.area);
class Square {
constructor(length) {
this.length = length;
}
get area() {
return this.length * this.length;
}
set area(value) {
this.area = value;
}
}
```
- 1: 100
- 2: ReferenceError
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
Unlike function declarations, class declarations are not hoisted. i.e, First You need to declare your class and then access it, otherwise it will throw a ReferenceError "Uncaught ReferenceError: Square is not defined".
**Note:** Class expressions also applies to the same hoisting restrictions of class declarations.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 50. What is the output of below code
```javascript
function Person() {}
Person.prototype.walk = function () {
return this;
};
Person.run = function () {
return this;
};
let user = new Person();
let walk = user.walk;
console.log(walk());
let run = Person.run;
console.log(run());
```
- 1: undefined, undefined
- 2: Person, Person
- 3: SyntaxError
- 4: Window, Window
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
When a regular or prototype method is called without a value for **this**, the methods return an initial this value if the value is not undefined. Otherwise global window object will be returned. In our case, the initial `this` value is undefined so both methods return window objects.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 51. What is the output of below code
```javascript
class Vehicle {
constructor(name) {
this.name = name;
}
start() {
console.log(`${this.name} vehicle started`);
}
}
class Car extends Vehicle {
start() {
console.log(`${this.name} car started`);
super.start();
}
}
const car = new Car("BMW");
console.log(car.start());
```
- 1: SyntaxError
- 2: BMW vehicle started, BMW car started
- 3: BMW car started, BMW vehicle started
- 4: BMW car started, BMW car started
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
The super keyword is used to call methods of a superclass. Unlike other languages the super invocation doesn't need to be a first statement. i.e, The statements will be executed in the same order of code.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 52. What is the output of below code
```javascript
const USER = { age: 30 };
USER.age = 25;
console.log(USER.age);
```
- 1: 30
- 2: 25
- 3: Uncaught TypeError
- 4: SyntaxError
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
Even though we used constant variables, the content of it is an object and the object's contents (e.g properties) can be altered. Hence, the change is going to be valid in this case.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 53. What is the output of below code
```javascript
console.log("🙂" === "🙂");
```
- 1: false
- 2: true
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
Emojis are unicodes and the unicode for smile symbol is "U+1F642". The unicode comparision of same emojies is equivalent to string comparison. Hence, the output is always true.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 54. What is the output of below code?
```javascript
console.log(typeof typeof typeof true);
```
- 1: string
- 2: boolean
- 3: NaN
- 4: number
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
The typeof operator on any primitive returns a string value. So even if you apply the chain of typeof operators on the return value, it is always string.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 55. What is the output of below code?
```javascript
let zero = new Number(0);
if (zero) {
console.log("If");
} else {
console.log("Else");
}
```
- 1: If
- 2: Else
- 3: NaN
- 4: SyntaxError
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
1. The type of operator on new Number always returns object. i.e, typeof new Number(0) --> object.
2. Objects are always truthy in if block
Hence the above code block always goes to if section.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 55. What is the output of below code in non strict mode?
```javascript
let msg = "Good morning!!";
msg.name = "John";
console.log(msg.name);
```
- 1: ""
- 2: Error
- 3: John
- 4: Undefined
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
It returns undefined for non-strict mode and returns Error for strict mode. In non-strict mode, the wrapper object is going to be created and get the mentioned property. But the object get disappeared after accessing the property in next line.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 56. What is the output of below code?
```javascript
let count = 10;
(function innerFunc() {
if (count === 10) {
let count = 11;
console.log(count);
}
console.log(count);
})();
```
- 1: 11, 10
- 2: 11, 11
- 3: 10, 11
- 4: 10, 10
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
11 and 10 is logged to the console.
The innerFunc is a closure which captures the count variable from the outerscope. i.e, 10. But the conditional has another local variable `count` which overwrites the ourter `count` variable. So the first console.log displays value 11.
Whereas the second console.log logs 10 by capturing the count variable from outerscope.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 57. What is the output of below code ?
- 1: console.log(true && 'hi');
- 2: console.log(true && 'hi' && 1);
- 3: console.log(true && '' && 0);
<details><summary><b>Answer</b></summary>
- 1: hi
- 2: 1
- 3: ''
Reason : The operator returns the value of the first falsy operand encountered when evaluating from left to right, or the value of the last operand if they are all truthy.
**Note:** Below these values are consider as falsy value
- 1: 0
- 2: ''
- 3: null
- 4: undefined
- 5: NAN
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 58. What is the output of below code ?
```javascript
let arr = [1, 2, 3];
let str = "1,2,3";
console.log(arr == str);
```
- 1: false
- 2: Error
- 3: true
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
Arrays have their own implementation of `toString` method that returns a comma-separated list of elements. So the above code snippet returns true. In order to avoid conversion of array type, we should use === for comparison.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 59. What is the output of below code?
```javascript
getMessage();
var getMessage = () => {
console.log("Good morning");
};
```
- 1: Good morning
- 2: getMessage is not a function
- 3: getMessage is not defined
- 4: Undefined
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
Hoisting will move variables and functions to be the top of scope. Even though getMessage is an arrow function the above function will considered as a varible due to it's variable declaration or assignment. So the variables will have undefined value in memory phase and throws an error '`getMessage` is not a function' at the code execution phase.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 60. What is the output of below code?
```javascript
let quickPromise = Promise.resolve();
quickPromise.then(() => console.log("promise finished"));
console.log("program finished");
```
- 1: program finished
- 2: Cannot predict the order
- 3: program finished, promise finished
- 4: promise finished, program finished
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
Even though a promise is resolved immediately, it won't be executed immediately because its **.then/catch/finally** handlers or callbacks(aka task) are pushed into the queue. Whenever the JavaScript engine becomes free from the current program, it pulls a task from the queue and executes it. This is the reason why last statement is printed first before the log of promise handler.
**Note:** We call the above queue as "MicroTask Queue"
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 61. What is the output of below code?
```javascript
console.log('First line')
['a', 'b', 'c'].forEach((element) => console.log(element))
console.log('Third line')
```
- 1: `First line`, then print `a, b, c` in a new line, and finally print `Third line` as next line
- 2: `First line`, then print `a, b, c` in a first line, and print `Third line` as next line
- 3: Missing semi-colon error
- 4: Cannot read properties of undefined
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
When JavaScript encounters a line break without a semicolon, the JavaScript parser will automatically add a semicolon based on a set of rules called `Automatic Semicolon Insertion` which determines whether line break as end of statement or not to insert semicolon. But it does not assume a semicolon before square brackets [...]. So the first two lines considered as a single statement as below.
```javascript
console.log('First line')['a', 'b', 'c'].forEach((element) => console.log(element))
```
Hence, there will be **cannot read properties of undefined** error while applying the array square bracket on log function.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 62. Write a function that returns a random HEX color
<details><summary><b>Solution 1 (Iterative generation)</b></summary>
<p>
```javascript
const HEX_ALPHABET = ["0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f"];
const HEX_PREFIX = "#";
const HEX_LENGTH = 6;
function generateRandomHex() {
let randomHex = "";
for(let i = 0; i < HEX_LENGTH; i++) {
const randomIndex = Math.floor(Math.random() * HEX_ALPHABET.length);
randomHex += HEX_ALPHABET[randomIndex];
}
return HEX_PREFIX + randomHex;
}
```
</p>
</details>
<details><summary><b>Solution 2 (One-liner)</b></summary>
<p>
```javascript
const HEX_PREFIX = "#";
const HEX_RADIX = 16;
const HEX_LENGTH = 6;
function generateRandomHex() {
return HEX_PREFIX + Math.floor(Math.random() * 0xffffff).toString(HEX_RADIX).padStart(HEX_LENGTH, "0");
}
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 63. What is the output of below code?
```javascript
var of = ['of'];
for(var of of of) {
console.log(of);
}
```
- 1: of
- 2: SyntaxError: Unexpected token of
- 3: SyntaxError: Identifier 'of' has already been declared
- 4: ReferenceError: of is not defined
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
In JavaScript, `of` is not considered as a reserved keyword. So the variable declaration with `of` is accepted and prints the array value `of` using for..of loop.
But if you use reserved keyword such as `in` then there will be a syntax error saying `SyntaxError: Unexpected token in`,
```javascript
var in = ['in'];
for(var in in in) {
console.log(in[in]);
}
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 64. What is the output of below code?
```javascript
const numbers = [11, 25, 31, 23, 33, 18, 200];
numbers.sort();
console.log(numbers);
```
- 1: [11, 18, 23, 25, 31, 33, 200]
- 2: [11, 18, 200, 23, 25, 31, 33]
- 3: [11, 25, 31, 23, 33, 18, 200]
- 4: Cannot sort numbers
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
By default, the sort method sorts elements alphabetically. This is because elemented converted to strings and strings compared in UTF-16 code units order. Hence, you will see the above numbers not sorted as expected. In order to sort numerically just supply a comparator function which handles numeric sorts.
```javascript
const numbers = [11, 25, 31, 23, 33, 18, 200];
numbers.sort((a, b) => a - b);
console.log(numbers);
```
**Note:** Sort() method changes the original array.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 65. What is the output order of below code?
```javascript
setTimeout(() => {console.log('1')}, 0);
Promise.resolve('hello').then(() => console.log('2'));
console.log('3');
```
- 1: 1, 2, 3
- 2: 1, 3, 2
- 3: 3, 1, 2
- 4: 3, 2, 1
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
When the JavaScript engine parses the above code, the first two statements are asynchronous which will be executed later and third statement is synchronous statement which will be moved to callstack, executed and prints the number 3 in the console. Next, Promise is native in ES6 and it will be moved to Job queue which has high priority than callback queue in the execution order. At last, since setTimeout is part of WebAPI the callback function moved to callback queue and executed. Hence, you will see number 2 printed first followed by 1.
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 66. What is the output of below code?
```javascript
console.log(name);
console.log(message());
var name = 'John';
(function message() {
console.log('Hello John: Welcome');
});
```
- 1: John, Hello John: Welcome
- 2: undefined, Hello John, Welcome
- 3: Reference error: name is not defined, Reference error: message is not defined
- 4: undefined, Reference error: message is not defined
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
IIFE(Immediately Invoked Function Expression) is just like any other function expression which won't be hoisted. Hence, there will be a reference error for message call.
The behavior would be the same with below function expression of message1,
```javascript
console.log(name);
console.log(message());
var name = 'John';
var message = function () {
console.log('Hello John: Welcome');
});
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 67. What is the output of below code?
```javascript
message()
function message() {
console.log("Hello");
}
function message() {
console.log("Bye");
}
```
- 1: Reference error: message is not defined
- 2: Hello
- 3: Bye
- 4: Compile time error
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
As part of hoisting, initially JavaScript Engine or compiler will store first function in heap memory but later rewrite or replaces with redefined function content.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 68. What is the output of below code?
```javascript
var currentCity = "NewYork";
var changeCurrentCity = function() {
console.log('Current City:', currentCity);
var currentCity = "Singapore";
console.log('Current City:', currentCity);
}
changeCurrentCity();
```
- 1: NewYork, Singapore
- 2: NewYork, NewYork
- 3: undefined, Singapore
- 4: Singapore, Singapore
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
Due to hositing feature, the variables declared with `var` will have `undefined` value in the creation phase so the outer variable `currentCity` will get same `undefined` value. But after few lines of code JavaScript engine found a new function call(`changeCurrentCity()`) to update the current city with `var` re-declaration. Since each function call will create a new execution context, the same variable will have `undefined` value before the declaration and new value(`Singapore`) after the declarion. Hence, the value `undefined` print first followed by new value `Singapore` in the execution phase.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 69. What is the output of below code in an order?
```javascript
function second() {
var message;
console.log(message);
}
function first() {
var message="first";
second();
console.log(message);
}
var message = "default";
first();
console.log(message);
```
- 1: undefined, first, default
- 2: default, default, default
- 3: first, first, default
- 4: undefined, undefined, undefined
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
Each context(global or functional) has it's own variable environment and the callstack of variables in a LIFO order. So you can see the message variable value from second, first functions in an order followed by global context message variable value at the end.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 70. What is the output of below code?
```javascript
var expressionOne = function functionOne() {
console.log("functionOne");
}
functionOne();
```
- 1: functionOne is not defined
- 2: functionOne
- 3: console.log("functionOne")
- 4: undefined
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
The function call `functionOne` is not going to be part of scope chain and it has it's own execution context with the enclosed variable environment. i.e, It won't be accessed from global context. Hence, there will be an error while invoking the function as `functionOne is not defined`.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 71. What is the output of below code?
```javascript
const user = {
name: 'John',
eat() {
console.log(this);
var eatFruit = function() {
console.log(this);
}
eatFruit()
}
}
user.eat();
```
- 1: {name: "John", eat: f}, {name: "John", eat: f}
- 2: Window {...}, Window {...}
- 3: {name: "John", eat: f}, undefined
- 4: {name: "John", eat: f}, Window {...}
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
`this` keyword is dynamic scoped but not lexically scoped . In other words, it doesn't matter where `this` has been written but how it has been invoked really matter. In the above code snippet, the `user` object invokes `eat` function so `this` keyword refers to `user` object but `eatFruit` has been invoked by `eat` function and `this` will have default `Window` object.
The above pit fall fixed by three ways,
1. In ES6, the arrow function will make `this` keyword as lexically scoped. Since the surrounding object of `this` object is `user` object, the `eatFruit` function will contain `user` object for `this` object.
```javascript
const user = {
name: 'John',
eat() {
console.log(this);
var eatFruit = () => {
console.log(this);
}
eatFruit()
}
}
user.eat();
```
The next two solutions have been used before ES6 introduced.
2. It is possible create a reference of `this` into a separate variable and use that new variable inplace of `this` keyword inside `eatFruit` function. This is a common practice in jQuery and AngularJS before ES6 introduced.
```javascript
const user = {
name: 'John',
eat() {
console.log(this);
var self = this;
var eatFruit = () => {
console.log(self);
}
eatFruit()
}
}
user.eat();
```
3. The `eatFruit` function can bind explicitly with `this` keyword where it refers `Window` object.
```javascript
const user = {
name: 'John',
eat() {
console.log(this);
var eatFruit = function() {
console.log(this);
}
return eatFruit.bind(this)
}
}
user.eat()();
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 72. What is the output of below code?
```javascript
let message = 'Hello World!';
message[0] = 'J';
console.log(message)
let name = 'John';
name = name + ' Smith';
console.log(name);
```
- 1: Jello World!, John Smith
- 2: Jello World!, John
- 3: Hello World!, John Smith
- 4: Hello World!, John
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
In JavaScript, primitives are immutable i.e. there is no way to change a primitive value once it gets created. So when you try to update the string's first character, there is no change in the string value and prints the same initial value `Hello World!`. Whereas in the later example, the concatenated value is re-assigned to the same variable which will result into creation of new memory block with the reference pointing to `John Smith` value and the old memory block value(`John`) will be garbage collected.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 73. What is the output of below code?
```javascript
let user1 = {
name : 'Jacob',
age : 28
};
let user2 = {
name : 'Jacob',
age : 28
};
console.log(user1 === user2);
```
- 1: True
- 2: False
- 3: Compile time error
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
In JavaScript, the variables such as objects, arrays and functions comes under pass by reference. When you try to compare two objects with same content, it is going to compare memory address or reference of those variables. These variables always create separate memory blocks hence the comparison is always going to return false value.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 74. What is the output of below code?
```javascript
function greeting() {
setTimeout(function() {
console.log(message);
}, 5000);
const message = "Hello, Good morning";
}
greeting();
```
- 1: Undefined
- 2: Reference error:
- 3: Hello, Good morning
- 4: null
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
The variable `message` is still treated as closure(since it has been used in inner function) eventhough it has been declared after setTimeout function. The function with in setTimeout function will be sent to WebAPI and the variable declaration executed with in 5 seconds with the assigned value. Hence, the text declared for the variable will be displayed.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 75. What is the output of below code?
```javascript
const a = new Number(10);
const b = 10;
console.log(a === b);
```
- 1: False
- 2: True
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 1
Eventhough both variables `a` and `b` refer a number value, the first declaration is based on constructor function and the type of the variable is going to be `object` type. Whereas the second declaration is primitive assignment with a number and the type is `number` type. Hence, the equality operator `===` will output `false` value.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 76. What is the type of below function?
```javascript
function add(a, b) {
console.log("The input arguments are: ", a, b);
return a + b;
}
```
- 1: Pure function
- 2: Impure function
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
Eventhough the above function returns the same result for the same arguments(input) that are passed in the function, the `console.log()` statement causes a function to have side effects because it affects the state of an external code. i.e, the `console` object's state and depends on it to perform the job. Hence, the above function considered as impure function.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 77. What is the output of below code?
```javascript
const promiseOne = new Promise((resolve, reject) => setTimeout(resolve, 4000));
const promiseTwo = new Promise((resolve, reject) => setTimeout(reject, 4000));
Promise.all([promiseOne, promiseTwo]).then(data => console.log(data));
```
- 1: [{status: "fullfilled", value: undefined}, {status: "rejected", reason: undefined}]
- 2: [{status: "fullfilled", value: undefined}, Uncaught(in promise)]
- 3: Uncaught (in promise)
- 4: [Uncaught(in promise), Uncaught(in promise)]
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
The above promises settled at the same time but one of them resolved and other one rejected. When you use `.all` method on these promises, the result will be short circuted by throwing an error due to rejection in second promise. But If you use `.allSettled` method then result of both the promises will be returned irrespective of resolved or rejected promise status without throwing any error.
```javascript
Promise.allSettled([promiseOne, promiseTwo]).then(data => console.log(data));
```
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 78. What is the output of below code?
```javascript
try {
setTimeout(() => {
console.log('try block');
throw new Error(`An exception is thrown`)
}, 1000);
} catch(err) {
console.log('Error: ', err);
}
```
- 1: try block, Error: An exception is thrown
- 2: Error: An exception is thrown
- 3: try block, Uncaught Error: Exception is thrown
- 4: Uncaught Error: Exception is thrown
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 3
If you put `setTimeout` and `setInterval` methods inside the try clause and an exception is thrown, the catch clause will not catch any of them. This is because the try...catch statement works synchronously, and the function in the above code is executed asynchronously after a certain period of time. Hence, you will see runtime exception without catching the error. To resolve this issue, you have to put the try...catch block inside the function as below,
```javascript
setTimeout(() => {
try {
console.log('try block');
throw new Error(`An exception is thrown`)
} catch(err) {
console.log('Error: ', err);
}
}, 1000);
```
You can use `.catch()` function in promises to avoid these issues with asynchronous code.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 79. What is the output of below code?
```javascript
let a = 10;
if(true){
let a = 20;
console.log(a, "inside");
}
console.log(a, "outside");
```
- 1: 20, "inside" and 20, "outside"
- 2: 20, "inside" and 10, "outside"
- 3: 10, "inside" and 10, "outside"
- 4: 10, "inside" and 20, "outside"
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 2
The variable "a" declared inside "if" has block scope and does not affect the value of the outer "a" variable.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
#### 80. What is the output of below code?
```javascript
let arr = [1,2,3,4,5,-6,7];
arr.length = 0;
console.log(arr);
```
- 1: 0
- 2: Undefined
- 3: null
- 4: [ ]
<details><summary><b>Answer</b></summary>
<p>
##### Answer: 4
The length of the array 'arr' has been set to 0, so the array becomes empty.
</p>
</details>
---
**[⬆ Back to Top](#table-of-contents)**
## Disclaimer
The questions provided in this repository are the summary of frequently asked questions across numerous companies. We cannot guarantee that these questions will actually be asked during your interview process, nor should you focus on memorizing all of them. The primary purpose is for you to get a sense of what some companies might ask — do not get discouraged if you don't know the answer to all of them — that is ok!
Good luck with your interview 😊
---
| List of 450 JavaScript Interview Questions | angular,core-javascript,interview-questions,interview-questions-and-answers,javascript,javascript-applications,javascript-interview-questions,js-interview-questions,react,vanilla-javascript | 2023-07-31T17:34:58Z | 2023-07-31T17:35:35Z | null | 1 | 0 | 1 | 0 | 2 | 5 | null | null | JavaScript |
Alireza-WebDeveloper/useImmerReducer-Bank-Account | main | null | null | bankaccount,javascript,reactjs,usereducer | 2023-08-04T10:18:55Z | 2023-08-04T10:16:17Z | null | 1 | 0 | 1 | 0 | 0 | 5 | null | null | TypeScript |
ShafiMohammad09/College-Canteen | main | # College Canteen Website
**Visit the deployed College Canteen Website: [Here](https://shafimohammad09.github.io/College-Canteen/)** 🚀
Welcome to the College Canteen Website project repository! This project is part of the Hacktoberfest 2023 with Community Exchange, an annual celebration of open-source contributions. 🎉
## Project Overview
This project is focused on enhancing the College Canteen website. We have identified several key areas for improvement:
1. **Navigation Bar**: Create a new and intuitive navigation bar to enhance user navigation throughout the website.
2. **Footer Section**: Design and implement a footer section to provide additional information and navigation options for users.
3. **Cart Section for Billing**: Develop a cart section where users can review their selected items and proceed with the billing process.
4. **Additional JavaScript Files**: Introduce new JavaScript files to implement additional features and enhance user interactivity.
5. **Media Queries for Responsiveness**: Add media queries to the CSS to ensure the website is responsive across various devices and screen sizes.
6. **Design Modifications**: Make necessary design modifications to improve the overall aesthetic and user experience.
7. **Login Page**: Create a new login page with a color palette that complements the existing website design.
8. **Animations**: Incorporate animations to add visual interest and improve user engagement. ✨
9. **Typewriter Effect**: Create a section with a typewriter effect that displays texts like "EAT.....CODE.....SLEEP......" to add a dynamic element to the website. ⌨️
## How to Contribute
We welcome contributions from the community to help enhance the College Canteen Website. You are encouraged to:
- Add any further files for assets and resources that may improve the web page interface and performance. 🛠️
- Introduce new languages or translations to make the website accessible to a wider audience. 🌐
Here's how you can get started:
1. **Fork the Repository**: Click on the "Fork" button to create your own copy of the repository.
2. **Choose a Task**: Pick a task from the list above (e.g., creating a new nav bar) that you'd like to work on.
3. **Create a New Branch**: Create a new branch for your feature or task: `git checkout -b feature-name`.
4. **Work on Your Task**: Make the necessary changes and improvements.
5. **Commit Your Changes**: Once you've completed your task, commit your changes with a descriptive message: `git commit -m 'Add feature-name'`.
6. **Push to Your Branch**: Push your changes to your branch: `git push origin feature-name`.
7. **Submit a Pull Request**: Go to the original repository and click on "New Pull Request". Provide a descriptive title and explain your changes.
**Important**: To be eligible for the Hacktoberfest perks by GitHub, contributors should make at least four pull requests or merges to the repository between 1st October to 31st October.
**Important Note**: Please do not change the main heading text "pragati" from the webpage. Doing so may lead to disqualification.
## Project Structure
- `/css`: Contains the CSS files for styling the website.
- `/js`: Houses JavaScript files for implementing features and interactivity.
- `/images`: Holds images and assets used in the website.
- `/docs`: Documentation and additional resources.
## License
This project is licensed under the [MIT License](LICENSE).
## Acknowledgements
We would like to thank all contributors for their valuable contributions to this project. 🙏
---
For more information or inquiries, feel free to contact us or visit the [College Canteen Website Documentation](https://example.com/docs). 📚
| "elevating user experience through an intuitive interface and interactive features. Contribute to this dynamic project and be part of a cutting-edge development team!" | collaborate,css,development,front-end-development,hacktoberfest,html,javascript,learn,react,webdev | 2023-08-05T02:03:55Z | 2024-02-03T06:42:07Z | null | 3 | 16 | 22 | 8 | 9 | 5 | null | MIT | HTML |
ritik2358/Portfolio-Ritik | main | <h2 align="center">
Portfolio Website<br/>
<a href="https://portfolio-ritik.vercel.app/" target="_blank">Ritik Raj</a>
</h2>
<!-- <p align="center">
<img width="959" alt="image" src="https://github.com/ritik2358/Portfolio-Ritik/assets/98156555/242f260b-1c01-469e-945c-74000104629a">
</p>-->
<!--<h3 align="center">
🔹
<a href="https://github.com/ritik2358/Portfolio-Ritik/issues">Report Bug</a>
🔹
<a href="https://github.com/ritik2358/Portfolio-Ritik/issues">Request Feature</a>
</h3> -->
## Welcome to My Portfolio 🚀
Hello there! Welcome to my portfolio website, where I showcase my journey and passion in the world of technology. As a final year Computer Science student I'm enthusiastic about coding, building innovative solutions, and exploring the vast possibilities in the digital realm.
<div align="center">
<img width="957" alt="image" src="https://github.com/ritik2358/Portfolio-Ritik/assets/98156555/d5cc30a8-579b-47c4-982c-519514b2136c">
</div>
## Built With 🛠️
This project was developed using a stack of technologies that empowers me to craft engaging and responsive web experiences:
- **React.js**: The heart of the website, ensuring dynamic components and smooth interactivity.
- **CSS3**: Custom styling for a unique and visually appealing design.
- **HTML5**: Structuring the content to ensure accessibility and semantic correctness.
- **Bootstrap**: Enhancing responsiveness and providing a solid foundation for styling.
- **Visual Studio Code**: My trusty code editor where all the magic happens.
- **Vercel**: The platform hosting this masterpiece, ensuring fast and reliable deployment.
## Features ✨
- 📖 **Multi-Page Layout**: Explore different sections, from projects to skills, in an organized manner.
- 🎨 **Styled with React-Bootstrap and Custom CSS**: Aesthetic design with easy-to-customize colors and components.
- 📱 **Fully Responsive**: Seamlessly experience the website on any device, be it a laptop, tablet, or phone.
## Getting Started 🚀
Ready to dive in? Follow these simple steps:
1. Clone this repository.
2. Ensure you have `node.js` and `git` installed on your system.
3. Installation: Run `npm install`.
4. Start the app: Run `npm start`.
Open [http://localhost:3000](http://localhost:3000) to view it in your browser.
## Customization 🎨
Feel free to make the portfolio your own! Navigate to `/src/components/` to find components and edit them to personalize the information.
## Show Your Support ⭐
If my portfolio caught your eye or inspired you in any way, give it a star to show your support and appreciation!
<!--<a href="https://www.buymeacoffee.com/ritik2358" target="_blank"><img src="https://cdn.buymeacoffee.com/buttons/v2/default-violet.png" alt="Buy Me A Coffee" height="60px" width="217px"></a>-->
| This is my Portfolio Website. | reactjs,vercel,css,html5,javascript,portfolio | 2023-08-02T18:29:39Z | 2024-03-09T15:46:28Z | null | 1 | 0 | 24 | 0 | 0 | 5 | null | null | JavaScript |
alihoushngi/Portfolio-v2 | main | This is a [Next.js](https://nextjs.org/) project bootstrapped with [`create-next-app`](https://github.com/vercel/next.js/tree/canary/packages/create-next-app).
## Getting Started
First, run the development server:
```bash
npm run dev
# or
yarn dev
# or
pnpm dev
```
Open [http://localhost:3000](http://localhost:3000) with your browser to see the result.
You can start editing the page by modifying `app/page.tsx`. The page auto-updates as you edit the file.
This project uses [`next/font`](https://nextjs.org/docs/basic-features/font-optimization) to automatically optimize and load Inter, a custom Google Font.
## Learn More
To learn more about Next.js, take a look at the following resources:
- [Next.js Documentation](https://nextjs.org/docs) - learn about Next.js features and API.
- [Learn Next.js](https://nextjs.org/learn) - an interactive Next.js tutorial.
You can check out [the Next.js GitHub repository](https://github.com/vercel/next.js/) - your feedback and contributions are welcome!
## Deploy on Vercel
The easiest way to deploy your Next.js app is to use the [Vercel Platform](https://vercel.com/new?utm_medium=default-template&filter=next.js&utm_source=create-next-app&utm_campaign=create-next-app-readme) from the creators of Next.js.
Check out our [Next.js deployment documentation](https://nextjs.org/docs/deployment) for more details.
| this is my portfolio web site developed by NextJs13 | front-end-development,frontend,javascript,nextjs,react | 2023-08-03T14:50:27Z | 2024-04-24T16:57:14Z | null | 2 | 0 | 48 | 0 | 0 | 5 | null | null | TypeScript |
gabrielfreitasc/Habits | main | <h1 align="center">Habits</h1>
<p>
<img alt="Projeto Habits" src="./web/public/preview.jpg" width="100%">
</p>
## 🚀 Tecnologias
Esse projeto foi desenvolvido com as seguintes tecnologias:
### **Web**
- TypeScript
- React & React DOM
- Tailwind CSS
- Radix
- Dayjs, clsx
- Axios
- Git e Github
- Figma
### **Mobile**
- TypeScript
- React Native
- Expo
- Nativewind
- Babel
- Tailwind CSS
- Dayjs, clsx
- Axios
- Git e Github
- Figma
### **Back-End**
- Fastify & Fastify Cors
- Prisma
- Dayjs
- TypeScript
- Zod
## 💻 Projeto
O Habits é um app para ajudar a desenvolver e acompanhar hábitos.
- [Acesse o projeto finalizado, online](https://gabrielfreitasc.github.io/Habits/)
## 🖼 Layout
Você pode vizualizar o layout do projeto através [DESSE LINK WEB](https://www.figma.com/file/pQwXGCScQDH3UowUlEFlNS/Habits-(i)-(Community)?type=design&node-id=6%3A343&mode=design&t=TGTnuSVgQkQF9qi7-1) e [DESSE LINK MOBILE](https://www.figma.com/file/ss9hSAmpDmcoFdaOvITjda/Habits-(i)-(Community)?type=design&node-id=1%3A2&mode=design&t=EM9DmhXFKx0E0dNq-1). é necessário ter conta no [Figma](https://figma.com) para acessa-lo.
---
Feito com ❤ by Gabriel Freitas - Siga-me no [Linkedin](https://www.linkedin.com/in/gabriel-freitasdev/)
| Habit Tracker | figma,git,typescript,deploy,eslint,javascript,tailwind,prisma,vitejs,habits | 2023-07-25T18:12:52Z | 2023-08-22T01:35:22Z | null | 1 | 0 | 5 | 0 | 0 | 5 | null | null | TypeScript |
knarkzel/salt | master | # salt
```
git clone https://github.com/knarkzel/salt && cd salt/
cargo run -- examples/01-hello_world.txt
```
| A Rust + JavaScript behemoth interpreter | interpreter,javascript,rust | 2023-07-28T11:53:56Z | 2023-07-30T16:57:33Z | null | 1 | 0 | 18 | 0 | 0 | 5 | null | null | Rust |
push42/fivem_dashboard | main | # FiveM Admin Dashboard
📊 
## **ATTENTION:** Downlaod the latest realease, i broke something in the main branch.
## Preview
> This project is a user-friendly, robust, and comprehensive admin dashboard for FiveM servers, designed with ❤️ by a dedicated FiveM enthusiast. Developed to polish my JavaScript and Database management skills, the dashboard aims to provide administrators with an insightful glance into the operations of their server. Your contributions are highly welcomed! Feel free to fork, use, and improve the project.
## Early Stages
This project is in it's early stages and doesn't offer that much yet, i will constantly work on updating it and add new features!
## Features
- **Server Status**: Keep track of your FiveM server's status using the included Trackyserver API integration. Easily monitor uptime, player count, and other important details.
- **Voting API**: Incorporated Voting API allows players to engage more deeply with your server.
- **Database Management**: Monitor and manage your server's database with easy-to-use tools.
- **Configurable**: Adjust the dashboard according to your specific needs for better server management.
## Technology Stack
The project is developed with PHP, HTML, CSS, JavaScript, and uses a MySQL database. This blend of technologies ensures a seamless, responsive, and powerful dashboard that adds value to your server administration experience.
## Getting Started
### Prerequisites
1. FiveM server
2. Trackyserver API key
3. PHP, MySQL, and a server to host the dashboard (e.g., Apache, Nginx)
4. Basic knowledge of HTML, CSS, and JavaScript for potential customization
### Installation
1. Clone the repository to your local machine.
2. Import the provided SQL file to your MySQL server.
3. Update the database connection inside the `.php` files with your specific server details and Trackyserver API key.
4. Host the files on your server, accessible through your domain or IP address.
5. You're all set! Visit the dashboard through your chosen access point.
## Contributing
This project is open source, and contributions are always welcomed! Whether it's bug reports, feature suggestions, or code improvements - all forms of contribution help.
1. Fork the project.
2. Create your feature branch (`git checkout -b feature/AmazingFeature`).
3. Commit your changes (`git commit -m 'Add some AmazingFeature'`).
4. Push to the branch (`git push origin feature/AmazingFeature`).
5. Open a pull request.
Please ensure your pull request adheres to the following guidelines:
- Write clear, meaningful commit messages.
- The pull request description should describe what your patch does.
- If your PR changes the UI, it should include "before" and "after" screenshots.
## Disclaimer
This project doesn't use or provide any sensitive data. Please make sure to change the Trackyserver API key and other personalizable settings to match your own before deploying this dashboard.
## License
Distributed under the MIT License. See `LICENSE` for more information.
## Contact
Thies Bergenthal - thiesmk2@gmail.com - Discord: push.42
Project Link: [https://github.com/reverseHaze/fivem_dashboard](https://github.com/reverseHaze/fivem_dashboard)
---
Crafted with ❤️ by a passionate FiveM server administrator. Happy gaming and server managing!
## Acknowledgements
- FiveM Community
- TrackyServer API
- All contributors who help to make this dashboard better!
| Simple 5M Admin Dashboard - (not finished) | PHP, HTML, CSS & Javascript | admin-dashboard,css,dashboard,fivem,html,html5,javascript,mysql,mysql-database,php | 2023-07-31T00:37:23Z | 2024-01-29T13:33:39Z | 2023-08-02T00:47:32Z | 2 | 3 | 48 | 0 | 2 | 5 | null | MIT | PHP |
Rakibhasan-programmer/portfolio-website | main | # Updated Portfolio
## [liveSite](https://rakibulhaasan.netlify.app/)
| This is my personal portfolio site. | javascript,react,react-bootstrap,reactjs | 2023-08-01T06:16:15Z | 2024-02-14T17:31:51Z | null | 1 | 0 | 32 | 0 | 0 | 5 | null | null | JavaScript |
kazi-naimul/rabbitmq | master | # RabbitMQ Helper
## Installation
To integrate the RabbitMQ Helper package into your project, use the following command:
```bash
yarn add @kazinaimul/rabbitmq
```
## RabbitMQ Server
You can use following docker file to create a RabbitMQ server:
```
FROM rabbitmq:3.12.0-management
RUN apt-get update
RUN apt-get install -y curl
RUN curl -L https://github.com/rabbitmq/rabbitmq-delayed-message-exchange/releases/download/v3.12.0/rabbitmq_delayed_message_exchange-3.12.0.ez > $RABBITMQ_HOME/plugins/rabbitmq_delayed_message_exchange-3.12.0.ez
RUN chown rabbitmq:rabbitmq $RABBITMQ_HOME/plugins/rabbitmq_delayed_message_exchange-3.12.0.ez
RUN rabbitmq-plugins enable --offline rabbitmq_delayed_message_exchange
RUN rabbitmq-plugins enable --offline rabbitmq_consistent_hash_exchange
```
# To be noted this package requires following plugins to enabled:
rabbitmq_delayed_message_exchange
rabbitmq_consistent_hash_exchange
## Usage
### Establishing Connection
In your Express app's `app.js` file, establish a connection to RabbitMQ using the following code:
```javascript
import { RabbitMQConnection } from '@kazinaimul/rabbitmq';
RabbitMQConnection.connect('RABBITMQ_CONNECTION_URL');
```
Replace `RABBITMQ_CONNECTION_URL` with your RabbitMQ server connection URL, formatted as `amqp://username:password@localhost:5672`.
### Publishing a Message
To publish a message, create a Publisher class by extending the provided `Publisher` class from the package. Here is an example:
```javascript
import { Publisher } from '@kazinaimul/rabbitmq';
export class PublishMessage extends Publisher {
constructor() {
const queueName = 'queue-name';
super(queueName);
}
async publish<MessageType>(message: MessageType): Promise<void> {
try {
const customOptions = {
exchange: `your-exchange_name`,
routingKey: queueName,
delay: 0,
exchangeType: "direct",
headers: {},
}; // Custom optional values, overwriting default options
await this.rabbitMQClient.publish(this.queueName, message, customOptions);
} catch (error) {
console.error('Error publishing messages:', error);
}
}
}
```
By default, the package uses the following options to publish a message:
```javascript
const defaultOptions = {
exchange: `Exchange_${queueName}`,
routingKey: queueName,
delay: 0,
exchangeType: "direct",
headers: {},
};
```
Here queueName is the given Queue Name while initialize the class.
You can customize these options as needed.
You can then use this class to publish messages anywhere in your application:
```javascript
const publisher = new PublishMessage();
publisher.publish(publishJson);
```
### Consuming Messages
To consume messages, create a Consumer class by extending the provided `Consumer` class from the package. Here is an example:
```javascript
import { Consumer } from '@kazinaimul/rabbitmq';
export class MyConsumer extends Consumer {
constructor() {
const queueName = 'queue-name';
const options = {
retry: true, // If true, messages will be queued again in case of an error (default is true)
retry_count: 3, // Maximum retry count, beyond which the message will be moved to an error queue
retry_delay: 0 // Delay in milliseconds for retries
};
super(queueName, options); // Options is an optional field
}
async execute<T extends object>(message: T): Promise<void> {
// Implement your own logic to handle the consumed message
}
}
```
Register your consumers in a file (e.g., `consumerRegister.ts`):
```javascript
import { MyConsumer } from './MyConsumer';
export const consumerRegister: any[] = [new MyConsumer()];
```
In your application, consume messages by iterating through the registered consumers:
```javascript
import { consumerRegister } from './consumerRegister';
// Consume messages from registered consumers
for (const consumer of consumerRegister) {
consumer.consume();
}
```
Now, the `MyConsumer` class will process messages from the specified queue.
Remember to replace `'queue-name'` with the actual queue name you want to use.
## Notes
- Replace placeholder values and adjust configurations according to your RabbitMQ setup.
- For further customization, refer to the provided classes in the package and their methods.
Feel free to reach out if you encounter any issues or have questions related to this package. Happy coding!
| RabbitMQ Helper: Simplifying RabbitMQ integration in Node.js. Easily connect, publish messages, and consume with easy retry mechanism. | javascript,nodejs,npm-package,rabbbitmq,rabbitmq-consumer,rabbitmq-publisher,rabbitmq-helper,typescript | 2023-08-06T17:46:48Z | 2024-01-06T14:58:00Z | 2023-12-24T06:02:44Z | 1 | 0 | 11 | 0 | 0 | 5 | null | null | TypeScript |
CyrilOlanolan/configurations | main | # @cyrilolanolan/configurations
_Monorepo for all of my personal configurations shared across different projects_
⚠️ This project is in active development. Check out the roadmap for next features to be added.
## ✨ Content
- ✔️ eslint-config-ts - [ESLint](https://eslint.org/) + [TypeScript](https://www.typescriptlang.org/) configuration with additional support for [React](https://reactjs.org/)
- ✔️ prettier-config - [Prettier](https://prettier.io/) configuration for code formatting
## 🏗️ Roadmap
| Feature | Status |
| ------------------- | ------ |
| eslint-config-ts | ✅ |
| prettier-config | ✅ |
| eslint-config-react | 🚧 |
| eslint-config-js | 🚧 |
## 🔢 Versioning
All configurations will be published with the same version number. Ensure that all packages from this repository are installed in the same version for compatibility.
| Monorepo for all of my personal configurations shared across different projects | configuration,eslint,javascript,prettier,react,typescript | 2023-07-22T11:36:59Z | 2024-04-08T07:00:06Z | null | 1 | 0 | 21 | 0 | 0 | 5 | null | MIT | JavaScript |
okinawaa/kr-age | main | # kr-age
## calculateAgeFromBirthDate6AndGenderCode
생년월일 6자리 + 성별코드 1자리를 받는 경우 이를 기반으로 `만나이`를 계산해줘요.
230619라면, 성별코드를 이용해 1923년생인지 2023년생인지 구분해줍니다.
```typescript
function calculateAgeFromBirthDate6AndGenderCode(birthDate6: string, genderCode: "1" | "2" | "5" | "6" | "3" | "4" | "7" | "8"): number;
```
## Examples
```typescript
calculateAgeFromBirthDate6AndGenderCode('970902',"1"); // 25
calculateAgeFromBirthDate6AndGenderCode('180902',"4"); // 4 2000년대 생으로 인색
calculateAgeFromBirthDate6AndGenderCode('180902',"1"); // 104 1900년대 생으로 인색
```
## is미성년자
현재 날짜를 기준으로 만나이를 고려하여 미성년자인지 판단해줘요.
```typescript
function is미성년자(birthDate6: string, genderCode: "1" | "2" | "5" | "6" | "3" | "4" | "7" | "8"): boolean;
```
## isBirthDate6
주어진 문자열이 올바른 생년월일 여섯자리인지 검증합니다.
```typescript
function isBirthDate6(birthDate: string): boolean;
```
## Examples
```typescript
isBirthDate6('980211'); // true
isBirthDate6('19960729'); // false
isBirthDate6('foobar'); // false
```
## isAge
주어진 문자열이 유효한 나이인지 검사합니다.
```typescript
function isAge(ageInput: string): boolean;
```
## Examples
```typescript
isAge('25'); // true
isAge('asd'); // false
isAge('24.3'); // false
```
| 한국 만나이에 관련된 함수를 제공해요. | age,esm,javascript,korea | 2023-07-27T17:37:09Z | 2023-07-28T06:54:18Z | null | 1 | 0 | 12 | 0 | 0 | 5 | null | null | TypeScript |
essential61/seqdiagram-ed | main | # seqdiagram-ed
seqdiagram-ed is a tool to produce UML 2.0 Sequence Diagrams. It uses Javascript, HTML and XSLT and runs completely in the browser.
It is hosted at [https://essential61.github.io/seqdiagram-ed/](https://essential61.github.io/seqdiagram-ed).
The examples.js file lists a number of examples described using the xml language created for this application. If anyone has some more examples I would be happy to add them.
| seqdiagram-ed is a tool to produce UML 2.0 Sequence Diagrams. It uses Javascript, HTML and XSLT and runs completely in the browser. | html5,javascript,sequence-diagram,svg,uml,xslt | 2023-07-30T15:23:26Z | 2024-02-05T12:00:35Z | null | 1 | 0 | 41 | 0 | 0 | 5 | null | GPL-3.0 | JavaScript |
Mo7ammedd/nodejs-e-commerce | main | # E-commerce Node.js
## Description
Secure E-commerce website with Node.js, Express js, and Mongoose.
## Run
To run the application, follow these steps:
1. Set up environmental variables:
Create a file named `.env` at the root of the project and add the following lines to it:
```
MONGO_URI=<your_mongo_uri>
JWT_SEC =<your_JWT_secret>
STRIPE_PRIVATE_KEY=<your_stripe_private_key>
```
Replace `<your_mongo_uri>`, `<your_JWT_secret>`, and `<your_stripe_private_key>` with the appropriate values you obtained for your MongoDB Atlas database, JWT secret, and Stripe private API key respectively.
2. Navigate to the "DB" folder:
Go to the "DB" folder in the project directory, and you'll find files related to your MongoDB database.
3. Fill your MongoDB Atlas database:
Use the files in the "DB" folder to populate your MongoDB Atlas database with the required data for the application to function correctly.
4. Install dependencies:
Open a terminal or command prompt in the root of the project directory, and run the following command to install the required dependencies:
```
npm install
```
5. Start the application:
After the installation is complete, run the following command in the terminal to start the application:
```
npm start
```
Now the application should be up and running. You can access it through your browser at the specified URL
```(usually http://localhost:3000)```.
Make sure your MongoDB Atlas database is properly connected, and you can interact with the application.
## Technology
The application is built with:
- Node.js version 18.17.0 LTS
- MongoDB version 7.4.0
- Express version 4.18.2
- bcrypt version 5.1.0
- dotenv version 16.3.1
- jsonwebtoken version 9.0.1
- mongoose version 7.4.0
- nodemon version 3.0.1
- route version 0.2.5
## Features
- User Authentication: We've implemented strong user authentication using bcrypt to protect user passwords effectively.
- Secure Transactions: Our platform uses encryption and HTTPS to ensure safe and confidential transactions.
- JWT Sessions: Enhancing security with JSON Web Tokens for efficient user session management.
- Scalable Architecture: Built for scalability, so it can handle a growing user base with ease.
- Efficient Database: Optimized database interactions with Mongoose for faster response times.
## Database
All the models can be found in the models directory created using mongoose.
### User Schema:
- username (String)
- email (String)
- password (String)
### Product Schema:
- title (String)
- description (String)
- img (String)
- categories (Array)
- size (Array)
- color (Array)
- price (Number)
- inStock (Boolean)
### Cart Schema:
- userId (String)
- products:
- [
- productId (String)
- quantity (Number) ->default: 1,
]
### Order Schema:
- userId (String)
- products:
- [
- productId (String)
- quantity (Number) ->default: 1,
]
- amount (Number)
- address (Object)
- status (String) -> default: "pending"
## License
[](http://badges.mit-license.org)
- MIT License
- Copyright 2023 © - MIT License
- [Mohammed Mostafa](https://github.com/mohammedd20)
- [Ali Nour](https://github.com/alin00r)
- [karem hamed](https://github.com/karemhamed)
- [Albassel Abobakr](https://github.com/Bassel-11)
| E-commerce website with Node.js, Express js, and Mongoose | bycrypt,expressjs,javascript,mongodb,mongoose,node-js | 2023-07-28T16:26:02Z | 2024-02-18T23:17:53Z | null | 1 | 0 | 14 | 0 | 0 | 5 | null | MIT | JavaScript |
bosombaby/WebGIS | master | # 一、html
[W3Schools 在线教程](https://www.w3schools.cn/)
# 二、css
[W3Schools 在线教程](https://www.w3schools.cn/)
# 三、bootstrap
[Bootstrap](https://getbootstrap.com/)
# 四、javascript
[JavaScript 教程](https://www.w3schools.cn/js/default.asp)
# 五、openlayers
## 5.1 入门
OpenLayers是一个用于在Web上显示交互式地图的JavaScript库（**数据经纬度**）。
- 开源免费：OpenLayers是一个完全开源的项目，可以免费使用和修改。
- 跨平台：OpenLayers可以在各种平台上运行，包括桌面浏览器、移动设备和服务器端。
- 显示多种地图服务：OpenLayers支持多种地图服务提供商，如OpenStreetMap、Bing Maps、Google Maps等。
- 丰富的地图控件和工具：OpenLayers提供了丰富的地图控件和工具，如缩放、平移、标注、测量等。
- 矢量数据的显示和编辑：OpenLayers支持矢量数据的显示和编辑，如点、线、面等。
- 支持GIS相关的功能：OpenLayers支持与GIS相关的功能，如投影转换、坐标系转换等。
- 可扩展性：OpenLayers可以通过插件和扩展来增强其功能和性能。
- 社区支持：OpenLayers有一个活跃的社区，提供了丰富的文档、示例和支持。
[OpenLayers v4.6.5 API - Class: Heatmap](https://openlayers.org/en/v4.6.5/apidoc/ol.layer.Heatmap.html)
[OpenLayers - Lastest](https://openlayers.org/)
```javascript
// 定义视图
const view = new ol.View({
center: ol.proj.fromLonLat([116.39, 39.9]),
zoom: 5
})
// 定义图层
const osmLayer = new ol.layer.Tile({
source: new ol.source.OSM()
})
const layerArray = [osmLayer]
// 定义地图
const map = new ol.Map({
target: 'map',
layers: layerArray,
view: view
})
```
## 5.2 坐标系转换
[地理坐标系与投影坐标系 | Cesium 入门教程](https://syzdev.cn/cesium-docs/advance/coordinate-introduction.html)
[EPSG.io: 坐标标准](https://epsg.io/)
[坐标转换proj](https://github.com/proj4js/proj4js)
```javascript
// 定义坐标系
proj4.defs("EPSG:32643", "+proj=utm +zone=43 +datum=WGS84 +units=m +no_defs");
// 定义视图
const view = new ol.View({
projection: 'EPSG:32643',
center: ol.proj.fromLonLat([116.39, 39.9]),
zoom: 5
})
```
- **openLayers默认使用的是Web墨卡托投影坐标系，也称为EPSG:3857坐标系。**
- **geojson默认使用EPSG:4326坐标系，也称为WGS84坐标系，是一种经纬度坐标系，用于描述地球表面的位置。**
## 5.3 栅格地图
### 5.3.1 stamen地图
Stamen Maps是一组基于OpenStreetMap数据的地图图层，提供了多种风格和颜色的地图，包括水彩风格、黑白风格、地形风格等。在OpenLayers中，可以通过ol.source.Stamen类型的图层数据源对象来加载Stamen Maps地图。
```javascript
const stamenSource = new ol.source.Stamen({
layer: 'watercolor' // 指定地图图层风格
});
const stamenLayer = new ol.layer.Tile({
source: stamenSource
});
map.addLayer(stamenLayer);
```
[stamen地图资源](http://maps.stamen.com/)
### 5.3.2 png图片
在OpenLayers中，可以使用ol.source.ImageStatic类型的图层数据源对象来加载静态图片。ol.source.ImageStatic类型的图层数据源对象可以通过url属性指定图片的路径，通过imageExtent属性指定图片在地图上的显示范围。
```javascript
const peopleSource = new ol.source.ImageStatic({
attributions: '<b>图片</b>',
url: './assets/image/people.png',
imageExtent: [13282294.85419822, 4117316.7495201533, 13298270.19310982, 4124482.7209218885],
})
const peopleLayer = new ol.layer.Image({
source: peopleSource
})
map.addLayer(peopleLayer)
```
### 5.3.3 空间要素
在OpenLayers中，Feature是表示地图上的空间要素（如点、线、面等）的对象。Feature对象包含了空间要素的几何信息和属性信息，可以通过样式来控制其在地图上的显示效果。Feature对象可以被添加到Vector Layer中，从而在地图上显示出来。Feature对象还可以用于进行空间分析、查询和编辑等操作。
```javascript
// 1 定义feature
const feature = new ol.Feature({
geometry: new ol.geom.Point([13282258.110811716, 4116011.921518731]),
})
const style = new ol.style.Style({
image: new ol.style.Icon({
src: './assets/image/tiger.png',
scale: 0.05
})
})
feature.setStyle(style)
// 2 定义source
const vectorSource = new ol.source.Vector({
features: [feature]
})
// 3 定义layer
const vectorLayer = new ol.layer.Vector({
source: vectorSource
})
// 4 添加layer
map.addLayer(vectorLayer)
```
### 5.3.4 WMS 地图服务
TileWMS和ImageWMS都是OpenLayers中用于显示WMS服务的图层类型，它们的主要区别在于请求方式和显示方式。
- TileWMS使用切片方式请求WMS服务，即将地图分成多个小块，每个小块对应一个WMS请求。这种方式可以提高地图的加载速度和性能，因为只请求当前视图范围内的数据。TileWMS图层通常用于显示栅格数据，如卫星影像、地形图等。
- ImageWMS使用单个请求方式请求WMS服务，即将整个地图作为一个请求发送给WMS服务。这种方式可以保证地图的完整性和一致性，但是会降低地图的加载速度和性能。ImageWMS图层通常用于显示矢量数据，如行政区划、道路、河流等。
- 因此，TileWMS和ImageWMS的主要区别在于请求方式和显示方式。TileWMS使用切片方式请求WMS服务，适用于栅格数据；ImageWMS使用单个请求方式请求WMS服务，适用于矢量数据。
**TileWMS**
```javascript
const tileSource = new ol.source.TileWMS({
url: 'http://localhost:8080/geoserver/company/wms',
params: { 'LAYERS': 'company:Indian_States' },
serverType: 'geoserver',
})
const tileLayer = new ol.layer.Tile({
source: tileSource
})
map.addLayer(tileLayer)
```
**ImageWMS**
```javascript
const imageSource = new ol.source.ImageWMS({
url: 'http://localhost:8080/geoserver/company/wms',
params: { 'LAYERS': 'company:Indian_States' },
})
const imageLayer = new ol.layer.Image({
source: imageSource
})
map.addLayer(imageLayer)
```
## 5.4 矢量地图
GeoJSON是一种基于JSON格式的地理空间数据交换格式，它可以用于描述点、线、面等地理空间要素的几何信息和属性信息。GeoJSON格式的数据可以被多种GIS软件和Web地图库（如OpenLayers、Leaflet等）所支持，可以方便地在Web地图上进行展示和分析。
GeoJSON格式的数据由一个JSON对象组成，其中包含了以下三个属性：
- type：表示GeoJSON对象的类型，可以是"Feature"、"FeatureCollection"、"Point"、"LineString"、"Polygon"等。
- geometry：表示地理空间要素的几何信息，可以是点、线、面等。
- properties：表示地理空间要素的属性信息，可以是名称、面积、长度等。
以下是一个GeoJSON格式的数据示例：
```json
{
"type": "Feature",
"geometry": {
"type": "Point",
"coordinates": [102.0, 0.5]
},
"properties": {
"name": "My Point"
}
}
```
在这个示例中，GeoJSON对象的类型为"Feature"，表示这是一个地理空间要素对象。geometry属性表示这个要素的几何信息，它是一个点类型，坐标为[102.0, 0.5]。properties属性表示这个要素的属性信息，包含了一个名称属性"name"，值为"My Point"。
### 5.4.1 文件内部读取
```json
//文件内部数据读入json数据
const lineJson = {
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {},
"geometry": {
"coordinates": [
[
119.32394397498649,
34.69532951371582
],
[
119.35729528683532,
34.71800553594258
],
[
119.40995525290981,
34.686257364557704
],
[
119.39014507519641,
34.655115837905655
],
[
119.33572977691847,
34.692649209500175
],
[
119.34801710233643,
34.699040560865626
]
],
"type": "LineString"
}
}
]
}
const lineSource = new ol.source.Vector({
features: (new ol.format.GeoJSON().readFeatures(lineJson))
})
const lineLayer = new ol.layer.Vector({
source: lineSource,
style: new ol.style.Style({
stroke: new ol.style.Stroke({
color: 'red', // 线条颜色
width: 5, // 线条宽度
lineDash: [5, 10], // 线条样式，数组中的数字表示实线和虚线的长度
lineCap: 'round', // 线条端点样式，可选值为butt、round、square
lineJoin: 'round' // 线条连接处样式，可选值为bevel、round、miter
})
})
})
map.addLayer(lineLayer)
```
### 5.4.2 外部url读取
```javascript
// 外部读取json数据
const polygonSource = new ol.source.Vector({
url: './assets/geojson/polygon.json',
format: new ol.format.GeoJSON()
})
const polygonLayer = new ol.layer.Vector({
source: polygonSource,
style: new ol.style.Style({
fill: new ol.style.Fill({
color: 'rgba(255, 255, 255, 0.5)'
}),
stroke: new ol.style.Stroke({
width: 5,
color: '#ffcc33',
})
})
})
map.addLayer(polygonLayer)
```
### 5.4.3 geoserver获取
```javascript
//使用geojson加载数据
const vectorSource = new ol.source.Vector({
format: new ol.format.GeoJSON(),
url: function (extent) {
return 'http://localhost:8080/geoserver/company/ows?service=WFS&version=1.0.0&request=GetFeature&typeName=company%3AIndian_States&maxFeatures=50&srsname=EPSG:3857&bbox=' + extent.join(",") + ',EPSG:3857&outputFormat=application%2Fjson'
},
strategy: ol.loadingstrategy.bbox
})
const vectorLayer = new ol.layer.Vector({
source: vectorSource
})
map.addLayer(vectorLayer)
```
### 5.4.4 热力图
```json
{
"type": "Feature",
"properties": {
"OBJECTID": 2,
"DepartmentCode": "164450333",
"VillageID": 5007,
"WardID": null,
"Code": "29565055008031140000HMPOLPUOFFPOS0002",
"POL_STAID": 2,
"POL_STAName": "Bruceept PS",
"PSCode": "PS - 02"
},
"geometry": {
"type": "Point",
"coordinates": [
76.926339999683975,
15.13819100027882
]
}
},
```
### 5.4.5 经纬度线标
```javascript
const graticule = new ol.Graticule({
map: map,
showLabels: true,
})
```
### 5.4.6 作业
```javascript
Q. Create a map having 5 lines, 3 polygons and 10 points.
each line should be representaion of different road.
(e.g. Highway, Villege Road, Rail road,etc. )
each polygon should be a representation of different landuse
(e.g. Residential area, Garden , Lake)
points should be a combination of Atms and bus stops
and then put an image of that point as a marker
```
```javascript
//添加矢量图层
const lygSource = new ol.source.Vector({
url: './assets/geojson/lyg.json',
format: new ol.format.GeoJSON()
})
const lygLayer = new ol.layer.Vector({
source: lygSource,
style: (feature) => {
const type = feature.getGeometry().getType()
const properties = feature.getProperties()
switch (type) {
case 'LineString':
return new ol.style.Style({
stroke: new ol.style.Stroke({
color: 'skyblue',
width: 5
})
})
case 'Polygon':
return new ol.style.Style({
fill: new ol.style.Fill({
color: 'rgba(255, 255, 255, 0.6)'
}),
stroke: new ol.style.Stroke({
color: 'pink',
width: 5
})
})
case 'Point':
return new ol.style.Style({
image: new ol.style.Icon({
src: './assets/image/tiger.png',
scale: 0.05
})
})
default:
break;
}
}
})
map.addLayer(lygLayer)
//获取所有layers
setTimeout(() => {
const layers = map.getLayers().getArray()
const line1 = layers[1].getSource().getFeatures()[0]
}, 2000)
```
## 5.5 事件交互
在OpenLayers中，可以使用事件交互来响应用户的交互操作，例如鼠标点击、移动、缩放等。以下是一些常用的事件交互：
- ol.interaction.Select：用于选择要素的交互。
- ol.interaction.Draw：用于绘制要素的交互。
- ol.interaction.Modify：用于修改要素的交互。
- ol.interaction.DragPan：用于拖拽地图的交互。
- ol.interaction.MouseWheelZoom：用于鼠标滚轮缩放地图的交互。
### 5.5.1 鼠标拖拽放大
```javascript
//事件交互
const dragBox = new ol.interaction.DragBox({})
//开始
dragBox.on('boxstart', (evt) => {
console.log('boxstart');
})
//结束
dragBox.on('boxend', (evt) => {
console.log('boxend');
view.fit(dragBox.getGeometry().getExtent(), map.getSize())
})
map.addInteraction(dragBox)
```
### 5.5.2 拖拽加载geojson文件
```javascript
const dragSource = new ol.source.Vector()
const dragLayer = new ol.layer.Vector({
source: dragSource
})
map.addLayer(dragLayer)
const dragDrop = new ol.interaction.DragAndDrop({
formatConstructors: [ol.format.GeoJSON],
source: dragSource
})
map.addInteraction(dragDrop)
```
### 5.5.3 绘制图形
```javascript
const drawSource = new ol.source.Vector()
const drawLayer = new ol.layer.Vector({
source: drawSource
})
map.addLayer(drawLayer)
const draw = new ol.interaction.Draw({
source: drawSource,
type: 'Polygon',
freehand: true
})
draw.on('drawend', (evt) => {
console.log(evt.feature.getGeometry().getCoordinates());
})
map.addInteraction(draw)
```
# 六、geoserver
## 6.1 通用style设置
SLD是GeoServer中的一个重要概念，它代表着“样式层描述”（Styled Layer Descriptor）。SLD是一种XML格式的文件，用于描述地图图层的样式和渲染规则。通过SLD文件，可以定义地图图层的颜色、符号、标签、透明度等属性，以便在地图上显示和渲染地理数据。
SLD文件通常包含以下几个部分：
1. 命名空间和元素声明：定义SLD文件的命名空间和元素。
2. FeatureTypeStyle：定义地图图层的样式和渲染规则。
3. Rule：定义地图图层的渲染规则，包括符号、标签、透明度等属性。
4. Symbolizer：定义地图图层的符号，包括点、线、面等。
通过SLD文件，可以实现地图图层的高度自定义和灵活性。GeoServer支持SLD 1.0和SLD 1.1两个版本，用户可以根据需要选择不同的版本。
[Styling — GeoServer 2.24.x User Manual](https://docs.geoserver.org/main/en/user/styling/index.html)
## 6.2 openlayers预览500
- 版本：jdk-17.0.5、geoserver - 2.23.1
- 解决方法：命令行启动，java -Djava.awt.headless=true -jar start.jar
## 6.3 跨域设置
[geoserver安装及跨域问题解决方案 - 掘金](https://juejin.cn/post/7088484003954556964)
# 七、Postgre SQL
## 7.1 前言
[Windows 上安装 PostgreSQL | 菜鸟教程](https://www.runoob.com/postgresql/windows-install-postgresql.html)
[WINDOWS 11 环境下安装POSTGRESQL](https://zhuanlan.zhihu.com/p/400220265)
:::info
- 电脑：windows 11
- 版本：10.23
:::
## 7.2 基础sql语句
### 7.2.1 增加
```sql
INSERT INTO product_mobile(
name, description, quantity, instock, price, front_camera)
VALUES ('xiaomi11','非常好',60,true,2000,1200)
```
### 7.2.2 删除
```sql
delete from product_mobile
where id=3
```
### 7.2.3 修改
```sql
update product_mobile
set description = '一般'
where id=1
```
### 7.2.4 查询
```sql
select * from product_mobile
where quantity >=60 and price<=2200
```
## 7.3 高级语法
## 7.4 bug
[https://gis.stackexchange.com/questions/331653/error-could-not-load-library-c-program-files-postgresql-11-lib-rtpostgis-2-5](https://gis.stackexchange.com/questions/331653/error-could-not-load-library-c-program-files-postgresql-11-lib-rtpostgis-2-5)
```sql
无法加载库 "D:/GIS/postgresql/10/lib/rtpostgis-2.4.dll": The specified module could not be found.
```
## 7.5 postgis
qgis制图导入postgre sql数据库之后，可以使用postgis 语句对数据进行处理
[Home](https://postgis.net/)
### 7.5.1 查询城市
```sql
SELECT allcities.*
FROM countries,allcities
WHERE ST_Contains(ST_Buffer(countries.geom,0.01),allcities.geom)
AND countries.admin = 'India';
```
### 7.5.2 转换单个区域坐标系
```sql
SELECT allcities.*
FROM countries,allcities
WHERE ST_Contains(ST_Buffer(ST_Transform(countries.geom,3857),1500),ST_Transform(allcities.geom,3857))
AND countries.admin = 'India';
```
- 在 EPSG:3857 坐标系中，距离的单位是米（m）。
- 在 EPSG:4326 坐标系中，距离的单位是度（degree）。
### 7.5.3 查询单个区域
```sql
SELECT ST_Area(ST_Transform(geom,3857)) FROM countries where admin = 'India'
```
### 7.5.4 计算点距离
```sql
SELECT ST_Distance(ST_Transform(a.geom,3857), ST_Transform(b.geom,3857))
FROM allcities a,allcities b
where a.name = 'New Delhi' and b.name = 'Mumbai'
```
# 八、php-ajax
## 8.1 XAMPP
[XAMPP Installers and Downloads for Apache Friends](https://www.apachefriends.org/)
XAMPP 是一个免费且易于安装的跨平台 Web 服务器解决方案（最流行的php开发环境），它包含 Apache、MySQL、PHP 和 Perl。它可以在 Windows、Linux 和 macOS 上运行，并且非常适合开发和测试 Web 应用程序。
这个下面没看
# 九、leaflet
## 9.1 前言
[Leaflet — an open-source JavaScript library for interactive maps](https://leafletjs.com/)
Leaflet是一个开源的JavaScript库，用于创建交互式地图（**数据纬经度**）。它是一个轻量级的库，具有高度的可定制性和可扩展性，可以在各种设备上运行。Leaflet支持各种地图提供商，包括OpenStreetMap、Mapbox和Google Maps等。它还提供了许多功能，如地图缩放、标记、弹出窗口、路径绘制等。
**Leaflet默认使用的坐标系是WGS84（World Geodetic System 1984），它的EPSG代码是4326。**
## 9.2 切换底图
[Leaflet Provider Demo](https://leaflet-extras.github.io/leaflet-providers/preview/)
## 9.3 绘制图形
```javascript
//加载polygon
const latlngs = [[37, -109.05], [41, -109.03], [41, -102.05], [37, -102.04]];
const polygon = L.polygon(latlngs, { color: 'red', fillColor: 'skyblue' }).addTo(map);
map.fitBounds(polygon.getBounds());
```
## 9.4 图形标记
Leaflet的Marker是一个用于在地图上添加标记的类。它有以下特点：
- 可以设置标记的位置、图标、大小、旋转角度等属性。
- 可以添加弹出窗口，当用户点击标记时会弹出。
- 可以设置标记的拖拽属性，允许用户拖动标记。
- 可以设置标记的动画效果，如弹跳、旋转等。
- 可以设置标记的事件监听器，如点击、拖拽等事件。
- 可以通过方法对标记进行操作，如移动、删除等。
- 可以与其他Leaflet类（如地图、图层等）进行交互，实现更复杂的功能。
```javascript
const map = L.map('map').setView([39.56, 116.20], 5);
L.tileLayer('https://tileserver.memomaps.de/tilegen/{z}/{x}/{y}.png', {
maxZoom: 18,
attribution: 'bosom'
}).addTo(map);
const dragMaker = L.marker([39.56, 116.20], {
title: '北京',
draggable: true
})
dragMaker.addTo(map)
dragMaker.on('dragstart', (e) => {
console.log('dragstart', e);
})
dragMaker.on('dragend', (e) => {
console.log('dragend', e);
})
dragMaker.on('drag', (e) => {
console.log('drag', e);
})
// movestart moveend
dragMaker.on('movestart', (e) => {
console.log('movestart', e);
})
dragMaker.on('moveend', (e) => {
console.log('moveend', e);
})
```
## 9.5 加载geojson
```javascript
const map = L.map('map').setView([39.56, 116.20], 5);
L.tileLayer('https://tile.openstreetmap.org/{z}/{x}/{y}.png', {
attribution: 'bosom'
}).addTo(map);
const data = {
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {
"name": "北京"
},
"geometry": {
"coordinates": [
116.42586641481421,
39.929189418847955
],
"type": "Point"
},
"id": 0
},
{
"type": "Feature",
"properties": {},
"geometry": {
"coordinates": [
120.28014276439222,
36.069516549809705
],
"type": "Point"
},
"id": 1
},
{
"type": "Feature",
"properties": {},
"geometry": {
"coordinates": [
121.38563288016263,
31.22203121318421
],
"type": "Point"
}
},
{
"type": "Feature",
"properties": {},
"geometry": {
"coordinates": [
119.14820726027642,
34.6321139210345
],
"type": "Point"
}
}
]
}
L.geoJSON(data, {}).bindPopup(function (layer) {
console.log(layer.feature.properties);
return '111'
}).addTo(map);
```
## 9.6 自定义maker
```javascript
const myIcon = L.icon({
iconUrl: './assets/icon/gugong.png',
iconSize: [60, 60],
iconAnchor: [22, 94],
popupAnchor: [10, - 100],
})
// 39.91668279062602, 116.39722805103676
const maker = L.marker([39.91668279062602, 116.39722805103676], { icon: myIcon }).addTo(map)
maker.bindPopup('<h1>故宫博物院</h1> <img src="./assets/icon/detail.png" alt="" width="200">').openPopup()
maker.bindTooltip("my tooltip text").openTooltip()
```
# 十、mapbox
[大屏地图：从瓦片到引擎，到手把手实战 - 掘金](https://juejin.cn/post/7171275204801331214)
mapbox 在 2022年6月 新出的规定，注册账号必须绑定一张国际信用卡。这个要求，就让很多国内小伙伴想试用的成本大大提升了。
Mapbox 是一个提供地图和地理空间数据的平台，它提供了一系列的 API 和 SDK，可以用于在 Web、移动设备和桌面应用程序中显示地图、进行地理空间分析和可视化等操作。
Mapbox 的地图数据是基于开放式数据源的，包括 OpenStreetMap 和其他开放式数据源。Mapbox 还提供了一些工具和服务，可以用于创建和编辑地图数据，例如 Mapbox Studio 和 Mapbox Editor。
Mapbox 的 API 和 SDK 支持多种编程语言和平台，包括 JavaScript、iOS、Android、Unity 等。开发者可以使用这些工具和服务，快速构建出具有地图和地理空间数据的应用程序。
除了地图和地理空间数据，Mapbox 还提供了一些其他的服务，例如地理编码、路线规划、地理围栏等。这些服务可以帮助开发者更方便地进行地理空间分析和应用程序开发。
总的来说，Mapbox 是一个功能强大的地图和地理空间数据平台，可以帮助开发者快速构建出具有地图和地理空间数据的应用程序，并提供了一系列的工具和服务，方便开发者进行地理空间分析和可视化。
| Web GIS是一种基于Web技术的地理信息系统，它将地理信息与Web技术相结合，可以实现地图浏览、查询、分析和可视化等功能。Web GIS在很多领域都有广泛的应用，如城市规划、环境保护、交通管理、农业生产等。它可以帮助用户更好地理解地理信息，提高决策效率，同时也可以促进地理信息的共享和交流。 | css,gis,html,javascript,web | 2023-07-27T14:10:04Z | 2023-07-27T14:10:00Z | null | 1 | 0 | 1 | 0 | 0 | 5 | null | null | JavaScript |
mohammadshahidbeigh/poetic-phrase-generator | main | # Poetic Phrase Generator
## Description
The Poetic Phrase Generator is a web application that generates poetic phrases and combines them with beautiful images based on your favorite activity and place. It utilizes the OpenAI GPT-3 model to generate insightful, witty, and satirical phrases in the style of Oscar Wilde. The app fetches random images from Unsplash to match the mood of the generated quotes. Simply input your name, favorite activity, and favorite place, and let the app create a unique poetic phase for you.
## Getting Started!
To run the Poetic Phrase Generator locally on your machine, follow these steps:
1. Clone this repository to your local machine using Git.
2. Open the `index.html` file in your web browser.
3. Customize the `name`, `favoriteActivity`, `favoritePlace`, and `temperature` variables in the `index.js` file to personalize your poetic phrases.
## For Quick start:
```
$ npm install
$ npm start
```
## Technologies Used
- HTML
- CSS (with Normalize.css)
- JavaScript (ES6)
- OpenAI GPT-3 API
- Unsplash API
- Google Fonts (Old Standard TT, Balsamiq Sans, Cinzel, Inconsolata, Sora, Lobster, Metal Mania, MuseoModerno, Noto Sans HK, Pacifico)
## Features
- Personalized poetic phrases generated in the style of Oscar Wilde.
- Beautiful images fetched from Unsplash to complement the generated quotes.
- Dynamic background based on the chosen place.
- Easy customization of name, favorite activity, and favorite place.
- Responsive design for a seamless experience on various devices.
## Usage
1. Open the Poetic Phrase Generator in your web browser.
2. Enter your name, favorite activity, and favorite place.
3. Adjust the temperature slider to control the creativity of the generated phrases.
4. Click the "Generate" button to see the poetic phrase and image.
5. Enjoy the delightful combinations of poetic phrases and images!
## Contributing
We welcome contributions to improve the Poetic Phrase Generator. To contribute, follow these steps:
1. Fork the repository.
2. Create a new branch for your feature or bug fix ` `.
3. Commit your changes and push them to your fork.
4. Submit a pull request to the original repository.
## License
This project is licensed under the [MIT License](LICENSE).
Feel inspired and enjoy the poetic phrases with the Poetic Phase Generator!
| This project uses the OpenAI and Unsplash APIs to generate a poetic phrase and display a background image. | css,html,javascript,openai,unsplash-api,learn,student-vscode | 2023-08-02T18:16:49Z | 2024-03-22T06:35:24Z | null | 2 | 1 | 36 | 0 | 4 | 5 | null | MIT | JavaScript |
zeynabkhayyati/type-spide | main | # type-spide
#### Increase your speed with type-speed ✌
| null | bootstrap,css,html,javascript,timer,typing-speed-test | 2023-07-24T16:36:59Z | 2023-07-24T16:48:19Z | null | 1 | 0 | 5 | 0 | 1 | 5 | null | null | HTML |
TheCommieAxolotl/pyotr | main | <p align="center">
<a href="https://www.npmjs.com/package/pyotr" target="__blank">
<img src="https://img.shields.io/npm/v/pyotr?style=flat&colorA=171717&colorB=efd94e" alt="Version">
</a>
<a href="https://www.npmjs.com/package/pyotr" target="__blank">
<img alt="Downloads" src="https://img.shields.io/npm/dm/pyotr?style=flat&colorA=171717&colorB=efd94e">
</a>
<a>
<img alt="Bundle" src="https://img.shields.io/bundlephobia/minzip/pyotr?style=flat&label=Bundle%20Size&labelColor=%23171717&color=%23efd94e">
</a>
<a href="https://github.com/TheCommieAxolotl/pyotr" target="__blank">
<img alt="Stars" src="https://img.shields.io/github/stars/TheCommieAxolotl/pyotr?style=flat&colorA=171717&colorB=efd94e">
</a>
</p>
---
Want to test it out? Check out the [Hello World example](https://stackblitz.com/edit/pyotr?file=index.js)!
---
# Pyotr
A tiny (< 2kb gzipped) 0-dependency HTTP wrapper with inbuilt routing and middleware support.
## Use
To instantiate a new Pyotr server, simply use `app`:
```ts
import http from "http";
import { app } from "pyotr";
const server = app(3000); // you can specify a port for local development
const server = app(http.createServer()); // you can also use an existing server
```
To add a route, use `app.attach` with a route provider:
```ts
import { app, route } from "pyotr";
import { html } from "pyotr/aura";
const server = app(3000);
server.attach(route("/", () => html`<h1>Hello, world!</h1>`));
```
If you want to use a whole directory as routes, instead of adding them one by one, you can use `app.use`:
```ts
import { resolve } from "node:path"
import { app } from "pyotr";
const server = app(3000);
const useOptions = {
recursive: true, // whether to recursively attach directories
prettyUrls: true, // whether or not to use pretty URLs (e.g. /about instead of /about.html)
guessTypes: true, // guess the MIME type of files (e.g. text/css for .css files)
};
server.use(resolve(process.cwd(), "./routes"), useOptions);
```
### Route Handlers
Route handlers are functions that are called when a request is made to a route. They are passed a [`PyotrRequest`]("https://github.com/TheCommieAxolotl/pyotr/blob/main/src/router/route.ts#L6-L12") object and may return a subset of Response options.
```ts
import { app, route } from "pyotr";
const server = app(3000);
server.attach(route("/", (req) => {
const { request, method, path, query, params } = req;
return {
type: string, // MIME type
content: string,
status: number, // HTTP status code
redirect: string, // redirect URL (should also set status to 302)
headers: Record<string, string>
};
}));
```
You can also update an existing route's handler by calling `route.update`:
```ts
const myRoute = route(...)
server.attach(myRoute);
myRoute.update((req) => {
// ...
});
``` | A tiny HTTP framework with inbuilt routing and middleware support. | https,router,http,express,javascript,middleware,nodejs,typescript | 2023-07-31T09:58:20Z | 2023-08-23T10:21:49Z | 2023-08-23T10:21:49Z | 1 | 0 | 62 | 0 | 0 | 5 | null | MIT | TypeScript |
mikaelvesavuori/5-minutes-or-less-solid | main | # 5 Minutes or Less: SOLID principles in TypeScript/JavaScript
## SOLID principles in TypeScript and JavaScript, demystified in less than 5 minutes each
Everyone who's coded for some time has probably heard about these principles, but do you know them?
If you were ever afraid to ask, here's your chance to understand them easily and in just a few minutes each!
## Five Minutes or Less
- [Design Patterns](https://github.com/mikaelvesavuori/5-minutes-or-less-design-patterns)
- [TypeScript/JavaScript patterns and features](https://github.com/mikaelvesavuori/5-minutes-or-less-typescript-js)
- [Refactoring](https://github.com/mikaelvesavuori/5-minutes-or-less-refactoring)
## The SOLID Principles
The principles in their mnemonic order:
- [Single Responsibility Principle](src/single-responsibility-principle.ts)
- [Open-Closed Principle](src/open-closed-principle.ts)
- [Liskov Substitution Principle](src/liskov-substitution-principle.ts)
- [Interface Segregation Principle](src/interface-segregation-principle.ts)
- [Dependency Inversion Principle](src/dependency-inversion-principle.ts)
**My recommended way to approach them, from easiest to "hardest", is:**
- [Single Responsibility Principle](src/single-responsibility-principle.ts)
- [Liskov Substitution Principle](src/liskov-substitution-principle.ts)
- [Interface Segregation Principle](src/interface-segregation-principle.ts)
- [Open-Closed Principle](src/open-closed-principle.ts)
- [Dependency Inversion Principle](src/dependency-inversion-principle.ts)
## Running the code
You can install the things with `npm install` and then just go at each file with `npx ts-node src/{filename}.ts`.
Or, if you're lazy, you can also copy the individual TS file's contents into the [TypeScript playground](https://www.typescriptlang.org/play) if you want to avoid cloning and installing anything at all.
| SOLID principles in TypeScript and JavaScript, demystified in less than 5 minutes each. | demos,design-patterns,javascript,js,learning,principles,solid,solid-principles,ts,typescript | 2023-08-05T08:30:12Z | 2023-08-17T13:41:36Z | null | 1 | 0 | 8 | 0 | 0 | 5 | null | null | TypeScript |
miltlima/goact | main | [](https://www.buymeacoffee.com/miltlima)
# goact cli
# Documentation
Goact is a command-line tool (CLI) that enables you to create pipeline stacks to automate workflows on GitHub Actions.
## Installation
Follow the steps below to install:
1. Download the Goact source code or clone the GitHub repository.
2. Navigate to the Goact project directory.
3. Compile the Goact code to create the executable:
```bash
go build
```
Move the executable to a folder that is in your system's PATH:
```bash
sudo mv goact /usr/local/bin
```
## Usage
Goact is designed to make it easy to create pipeline stacks in GitHub Actions. With the create command, you can configure GitHub Actions and generate essential files for your actions.
## Command create
The create command is used to create the GitHub Actions configuration for a specific pipeline stack.
```bash
goact create --stack <STACK_NAME>
```
Replace <STACK_NAME> with the name of the stack you want to create, for example, node.js, python, java, golang or ruby.
```bash
goact create --stack node.js
```
## Optional
Optionally, you can create dockerfile with stack desired for you projects per example you choose ruby as a stack add the flag -d will create a dockerfile for ruby
```bash
goact create --stack ruby -d
```
| Goact - is a CLI to create default github actions | github-actions,golang,java,javascript,nodejs,ruby | 2023-07-22T01:59:37Z | 2023-09-18T18:40:16Z | 2023-09-18T18:41:25Z | 1 | 3 | 22 | 0 | 0 | 5 | null | MIT | Go |
chaseottofy/vercel-nav | main | # Vercel Navbar Recreation
**vercel.com/design**
*For educational and showcase purposes only*
## Compare to original
### [View Original](https://vercel.com/)
#### [View Recreation Codepen](https://codepen.io/chaseottofy/pen/jOQevOV)
#### [View Recreation Github Pages](https://chaseottofy.github.io/vercel-nav/)
---
## All Features Implemented
- Pixel perfect representation
- Navbar toggles between fixed and relative positioning depending on scroll position.
- Navbar links are functional.
- Responsive design.
- Animations implemented.
- Toggles between switch elements on scroll over relavent sections.
- Zero dependencies.
- **SVGs on Home screen from Vercel.**
## Optimized
## Built With
- TypeScript
- JavaScript
- HTML & CSS
---
## Installation and Usage
This project utilizes a bare-bones tsup configuration.
**install**
```bash
git clone https://github.com/username/reponame.git
cd reponame
npm install
```
**use**
```bash
npm run predeploy
```
- Predeploy will bundle typescript, and copy minified html/css/ect to /dist/ folder
- Open /dist/index.html
---
## License
This project is open-source and available to everyone under the [MIT License](LICENSE).
| Recreation of Navbar featured on vercel.com/design | design,javascript,nav,navbar,typescript,typescript-component,web-design,vercel-design,vercel-navbar | 2023-07-27T22:55:08Z | 2023-07-27T23:41:49Z | null | 1 | 0 | 7 | 0 | 1 | 5 | null | MIT | CSS |
ZainAsif767/car_showcase | master | This is a [Next.js](https://nextjs.org/) project bootstrapped with [`create-next-app`](https://github.com/vercel/next.js/tree/canary/packages/create-next-app).
# CarHub
In this repository, you will find a project that uses NEXTjs, ReactJS, TailwindCss, and TypeScript. The CarHub is a static webpage that showcases cars with their classifications and specifications, designed for rental services.
## Getting Started
Clone the repository: ```https://github.com/ZainAsif767/car_showcase.git```\
Install the dependencies:
```bash
npm install
#or
yarn install
#or
pnpm install
```
Now, run the development server:
```bash
npm run dev
# or
yarn dev
# or
pnpm dev
```
Open [http://localhost:3000](http://localhost:3000) with your browser to see the result.
## Learn More
To learn more about Next.js, take a look at the following resources:
- [Next.js Documentation](https://nextjs.org/docs) - learn about Next.js features and API.
- [Learn Next.js](https://nextjs.org/learn) - an interactive Next.js tutorial.
You can check out [the Next.js GitHub repository](https://github.com/vercel/next.js/) - your feedback and contributions are welcome!
## Deploy on Vercel
The easiest way to deploy your Next.js app is to use the [Vercel Platform](https://vercel.com/new?utm_medium=default-template&filter=next.js&utm_source=create-next-app&utm_campaign=create-next-app-readme) from the creators of Next.js.
Check out our [Next.js deployment documentation](https://nextjs.org/docs/deployment) for more details.
## Contributing
Contributions are welcome! If you find any issues or have suggestions for improvements, please open an issue or submit a pull request.
| null | javascript,nextjs,react,tailwindcss,typescript | 2023-07-30T11:34:42Z | 2023-08-18T18:06:58Z | null | 1 | 0 | 38 | 0 | 0 | 5 | null | null | TypeScript |
MozamelJawad/Testing-practice | main | # Testing-practice
In **Testing-practice** project, I write a few practical tests for JavaScript functions using the Jest library. | In Testing-practice project, I write a few practical tests for JavaScript functions using the Jest library. | aaa-testing,functions,javascript,jest | 2023-07-26T09:05:28Z | 2023-07-26T12:49:18Z | null | 1 | 0 | 9 | 0 | 0 | 5 | null | MIT | JavaScript |
khushi11saxena/Explore-India | main | # Explore India
## Description
Explore India is a static frontend website for travelers interested in visiting India. This website aims to provide an easy and engaging way to plan and visualize your trip. It offers an interactive platform to get detailed information about various tourist destinations, local cuisines, accommodation, and cultural experiences in India.
Built with pure HTML, CSS, and JavaScript, this project showcases the beauty and diversity of India, and promotes its unique culture and heritage.
## Features
- Detailed information about different tourist spots across India
- A gallery of beautiful images to visualize each place
- Contact form for any inquiries or feedback
- Responsive design for all device types (BEST TO BE USED ON DESKTOP )
## Technology Stack
This project is built using pure HTML, CSS, and JavaScript without the use of any frameworks or libraries.
- **HTML5**: For structuring the website
- **CSS3**: For styling the website, making it responsive and appealing to users
- **JavaScript**: To make the website interactive and dynamic
## Local Setup
1. **Clone the repository:**
- `git clone https://github.com/khushi11saxena/Explore-India`
2. **Open https://khushi11saxena.github.io/Explore-India/ in your browser:**
## Contact
If you want to contact me you can reach me at (https://www.linkedin.com/in/khushi-saxena-542ba2216/).
| A Website that showcases the best tourist places to visit in India. | css3,figma,html5,javascript | 2023-07-22T11:44:27Z | 2023-11-23T18:44:48Z | null | 1 | 0 | 52 | 0 | 0 | 5 | null | null | HTML |
Rashmi7205/blog-website | main | # Blog Website
Welcome to the Blog Website repository! This project is a simple blog website developed using [insert the technology stack used].
## Folder Structure
The project is organized with the following folder structure:
## Frontend Folder Structure
```
blog-website/
|-- public/
| |-- index.html
| |-- favicon.ico
| |-- ...
|-- src/
| |-- assets/
| | |-- images/
| | | |-- blog-post-1.jpg
| | | |-- blog-post-2.jpg
| | | |-- ...
| |-- components/
| | |-- Header/
| | | |-- Header.js
| | | |-- Header.css
| | |-- Post/
| | | |-- Post.js
| | | |-- Post.css
| | |-- ...
| |-- pages/
| | |-- Home/
| | | |-- Home.js
| | | |-- Home.css
| | |-- About/
| | | |-- About.js
| | | |-- About.css
| | |-- ...
| |-- App.js
| |-- App.css
| |-- index.js
|-- .gitignore
|-- package.json
|-- README.md
|-- ...
```
## Backend Folder Structure
```
blog-website/
|-- backend/
| |-- node_modules/
| |-- src/
| | |-- controllers/
| | | |-- postController.js
| | | |-- userController.js
| | |-- models/
| | | |-- Post.js
| | | |-- User.js
| | |-- routes/
| | | |-- postRoutes.js
| | | |-- userRoutes.js
| | |-- app.js
| | |-- config.js
| | |-- server.js
|-- public/
|-- src/
| |-- assets/
| | |-- images/
| | | |-- blog-post-1.jpg
| | | |-- blog-post-2.jpg
| | | |-- ...
| |-- components/
| | |-- Header/
| | | |-- Header.js
| | | |-- Header.css
| | |-- Post/
| | | |-- Post.js
| | | |-- Post.css
| | |-- ...
| |-- pages/
| | |-- Home/
| | | |-- Home.js
| | | |-- Home.css
| | |-- About/
| | | |-- About.js
| | | |-- About.css
| | |-- ...
| |-- App.js
| |-- App.css
| |-- index.js
|-- .gitignore
|-- package.json
|-- README.md
|-- ...
```
<pre style="color:red">
controllers: Controllers handling business logic.
postController.js: Controller for managing blog posts.
userController.js: Controller for managing users.
models: Database models.
Post.js: Model for blog posts.
User.js: Model for users.
routes: API routes.
postRoutes.js: Routes for blog posts.
userRoutes.js: Routes for users.
app.js: Express application setup.
config.js: Configuration file (e.g., database connection).
server.js: Main server file.
</pre>
| null | blog,expressjs,javascript,mongodb,nodejs,react,redux,rest-api | 2023-08-07T16:06:59Z | 2024-01-23T04:56:47Z | null | 1 | 0 | 33 | 0 | 0 | 5 | null | null | JavaScript |
volcengine/pulumi-volcengine | main | # Pulumi Volcengine Resource Provider
The Pulumi Volcengine Resource Provider lets you manage [Volcengine](https://www.volcengine.com/) resources.
## Installing
### Install volcengine provider
```bash
pulumi plugin install resource volcengine --server github://api.github.com/volcengine
```
This package is available for several languages/platforms:
### Node.js (JavaScript/TypeScript)
To use from JavaScript or TypeScript in Node.js, install using either `npm`:
```bash
npm install @volcengine/pulumi
```
or `yarn`:
```bash
yarn add @volcengine/pulumi
```
### Python
To use from Python, install using `pip`:
```bash
pip install pulumi_volcengine
```
### Go
To use from Go, use `go get` to grab the latest version of the library:
```bash
go get github.com/volcengine/pulumi-volcengine/sdk/go/...
```
### .NET
To use from .NET, install using `dotnet add package`:
```bash
dotnet add package Volcengine.Pulumi.Volcengine
```
## Configuration
The following configuration points are available for the `volcengine` provider:
- `volcengine:accessKey` (environment: `VOLCENGINE_ACCESS_KEY`) - the API key for `volcengine`
- `volcengine:secretKey` (environment: `VOLCENGINE_SECRET_KEY`) - the API Secret Key for `volcengine`
- `volcengine:region` (environment: `VOLCENGINE_REGION`) - the region in which to deploy resources
[//]: # (## Reference)
[//]: # ()
[//]: # (For detailed reference documentation, please visit [the Pulumi registry](https://www.pulumi.com/registry/packages/volcengine/api-docs/).)
| An Volcengine Pulumi resource package, providing multi-language access to Volcengine | infrastructure,infrastructure-as-code,pulumi,sdk,terraform,golang,javascript,python,typescript,volcengine | 2023-07-25T06:35:17Z | 2024-01-03T06:19:54Z | 2024-01-03T06:19:54Z | 4 | 1 | 48 | 0 | 1 | 5 | null | Apache-2.0 | Python |
atharv01h/Stackoverflow-clone | master | # Stack OverFlow Clone
This website is a question forum and made to look like Stack Overflow.
The Code of this Project is Completely Written by Atharv Hatwar
## Installation
Fork and clone the repo and follow the below steps:
Install Node.js
Open client and server directories in VS code
Install Dependencies using the command
```Start
cd client
npm start
```
# Usage
*React js
Node js
Express js
MongoDb
Redux
Json web token*
## Contributing
Pull requests are welcome. For major changes, please open an issue first
to discuss what you would like to change.
Please make sure to update tests as appropriate.
## License
[MIT](https://choosealicense.com/licenses/mit/)
| This website is a question forum and made to look like Stack Overflow. | javascript,mern-project,mern-stack,mern-stack-development,projects,stack,stackoverflow | 2023-07-29T12:24:00Z | 2023-07-30T07:57:31Z | null | 1 | 1 | 7 | 0 | 4 | 5 | null | null | JavaScript |
krestaino/podcast-xml-parser | main | <!-- HIDE_SECTION_START -->
[](https://github.com/krestaino/podcast-xml-parser)
[](https://www.npmjs.com/package/podcast-xml-parser)
[](https://raw.githubusercontent.com/krestaino/podcast-xml-parser/main/LICENSE.md)
[](https://github.com/krestaino/podcast-xml-parser/actions/workflows/build.yml)
[](https://codecov.io/github/krestaino/podcast-xml-parser)
[](https://podcast-xml-parser.kmr.io/)
<!-- HIDE_SECTION_END -->
# podcast-xml-parser
Parse podcast feeds in browsers, React Native, or Node.js environments.
- **📜 Simple Parsing:** Parse XML podcast feeds into JavaScript objects.
- **🔗 Versatile Input:** Parse from URLs, iTunes IDs, or directly from XML strings.
- **💻 Cross-platform:** Designed to work in browsers, React Native, and Node.js.
- **🚫 Graceful Handling:** In cases of missing elements in the XML feed, the parser returns empty strings instead of throwing errors.
- **🎧 Support for iTunes:** Additional details can be fetched from iTunes.
- **🔢 Partial Feed Support:** Allows fetching and parsing a specific byte range of a feed.
- **🌐 OPML Parsing:** Extracts podcast feed URLs from OPML outlines, commonly used for podcast subscriptions.
<!-- HIDE_SECTION_START -->
## Live Demo
Want to see the library in action? Check the [demo](https://podcast-xml-parser.kmr.io/) and test out `podcast-xml-parser` with various XML podcast feeds.
<!-- HIDE_SECTION_END -->
## Requirements
This library uses the [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API). In environments where the Fetch API is not available, you need to use a polyfill. Notably, Node.js 17 or lower and Internet Explorer do not support the Fetch API. See [here](https://github.com/BuilderIO/this-package-uses-fetch) for more information about how to polyfill the Fetch API.
## Installation
You can install the library using `npm` or `yarn`.
```bash
npm install podcast-xml-parser
# or
yarn add podcast-xml-parser
```
## Basic Example
```javascript
import { podcastXmlParser } from "podcast-xml-parser";
const url = new URL("https://feeds.simplecast.com/dHoohVNH");
const { podcast } = await podcastXmlParser(url);
console.log(podcast.title); // "Conan O’Brien Needs A Friend"
```
## Usage `podcastXmlParser()`
**Purpose**: Parses a podcast's XML feed to retrieve podcast and episode details.
**Parameters**:
- `source` _(URL | number | string)_: The source of the XML content. Can be a URL object, an iTunes ID, or an XML string.
- `config` _(Config)_: Configuration options for the request, like request size, request headers, pagination, or to additionally return iTunes details.
**Returns**:
A promise that resolves with an object containing:
- `podcast`: Details of the podcast.
- `episodes`: An array of episode details.
- `itunes?`: Additional iTunes details.
**Signature**:
```typescript
podcastXmlParser(source: URL | number | string, config?: Config): Promise<{
podcast: Podcast;
episodes: Episode[];
itunes?: Itunes;
}>
```
## Usage `podcastOpmlParser()`
**Purpose**: Parses an OPML outline to extract podcast feed URLs and optional titles.
**Parameters**:
- `source` _(URL | string)_: The source of the OPML content. Can be a URL object or an XML string.
**Returns**:
A promise that resolves with an array of objects, each containing a feed URL and an optional title extracted from the OPML outline.
**Signature**:
```typescript
podcastOpmlParser(source: URL | string): Promise<{ title?: string; url: string }[]>
```
## Configuration Options
The `podcastXmlParser` function accepts a configuration object as its second parameter, allowing you to customize various aspects of the parsing process.
#### `requestHeaders`: Record<string, string>
Allows you to set custom headers for the HTTP request when fetching the XML feed. This can be useful for setting a custom `User-Agent` or other headers required by the server. If no `User-Agent` is specified, the default user agent `podcast-xml-parser/{version}` is used, where `{version}` is the version of the library.
```javascript
const config = {
requestHeaders: {
"User-Agent": "MyCustomUserAgent/1.0",
},
}; // Sets a custom User-Agent header
```
#### `requestSize`: number
Specifies the number of bytes to fetch from the XML feed, allowing you to limit the size of the request. Useful for improving response times when you only need a portion of the feed.
```javascript
const config = { requestSize: 50000 }; // First 50,000 bytes of the feed
```
#### `start`: number
The starting index for episode pagination. Combined with the `limit` option, this allows you to paginate through the episodes in the feed.
```javascript
const config = { start: 0, limit: 10 }; // Retrieves the last 10 episodes
```
#### `limit`: number
The number of episodes to retrieve from the starting index. Used in conjunction with the `start` option for pagination.
```javascript
const config = { start: 5, limit: 5 }; // Retrieves episodes 6 through 10
```
#### `itunes`: boolean
A boolean flag to control whether iTunes data is retrieved. If set to `true`, the parser will fetch additional details from iTunes based on the podcast's feed URL.
```javascript
const config = { itunes: true }; // Fetch additional details from iTunes
```
## Examples
### From a URL
When parsing a URL, you must call `new URL()` otherwise the library will try to parse the URL as XML, rather than the contents of the URL.
```javascript
import { podcastXmlParser } from "podcast-xml-parser";
const url = new URL("https://feeds.simplecast.com/dHoohVNH"); // Use 'new URL()' to ensure the library treats it as a URL
const { podcast, episodes, itunes } = await podcastXmlParser(url);
console.log(podcast.title); // "Conan O’Brien Needs A Friend"
console.log(episodes[episodes.length - 1].title); // "Introducing Conan’s new podcast"
console.log(itunes.collectionId); // 1438054347
```
### From an iTunes ID
When parsing from an iTunes ID, make sure the value is a number.
```javascript
import { podcastXmlParser } from "podcast-xml-parser";
const collectionId = 1438054347; // iTunes collectionId
const { podcast } = await podcastXmlParser(collectionId);
console.log(podcast.title); // "Conan O’Brien Needs A Friend"
```
### From an XML string
You can read from the filesystem or pass a string.
#### From the filesystem
```javascript
import fs from "fs";
import { podcastXmlParser } from "podcast-xml-parser";
const xmlData = fs.readFileSync("test.xml", "utf-8");
const { podcast } = await podcastXmlParser(xmlData);
console.log(podcast.title);
```
#### From a string
```javascript
import { podcastXmlParser } from "podcast-xml-parser";
const xmlString = `
<rss version="2.0">
<channel>
<title>Podcast Title</title>
<item>
<title>Episode 1 Title</title>
</item>
</channel>
</rss>
`;
const { podcast, episodes } = await podcastXmlParser(xmlString);
console.log(podcast.title); // Podcast Title
console.log(episodes[0].title); // Episode 1 Title
```
### iTunes Data
You can optionally return additional data from iTunes. This can be useful for obtaining consistent and reasonable artwork. Some podcast feeds use large uncompressed artwork. The artwork returned from the iTunes response is compressed and standardized, making it much easier to work with. You can see the data structure in the [iTunes Search API documentation](https://developer.apple.com/library/archive/documentation/AudioVideo/Conceptual/iTuneSearchAPI/UnderstandingSearchResults.html). Enabling this feature requires an additional network request.
```javascript
import { podcastXmlParser } from "podcast-xml-parser";
const url = new URL("https://feeds.simplecast.com/dHoohVNH"); // From a URL
const config = { itunes: true }; // Enable additional details from iTunes
const { podcast, itunes } = await podcastXmlParser(url, config);
console.log(podcast.title); // "Conan O’Brien Needs A Friend"
console.log(itunes.artworkUrl600); // "https://is1-ssl.mzstatic.com/image/thumb/Podcasts116/v4/0f/89/ef/0f89ef97-d10c-4b90-6127-ccee04776d54/mza_5706050832923787468.jpg/600x600bb.jpg"
```
**Note**: If the podcast is not available on iTunes, the `itunes` property in the returned object from the `podcastXmlParser()` function will be `undefined`.
### Partial Feed
You can limit the request size of the XML fetch to improve response times. This can be useful to return the latest episodes quickly when you don't need the entire feed.
```javascript
import { podcastXmlParser } from "podcast-xml-parser";
const url = new URL("https://feeds.simplecast.com/54nAGcIl"); // From a URL with a huge feed
const config = { requestSize: 50000, itunes: true }; // First 50,000 bytes of the feed
const { episodes, itunes } = await podcastXmlParser(url, config);
console.log(episodes.length !== itunes.trackCount); // true
```
**Note**: To use the `requestSize` option, it is not necessary to enable the iTunes data fetch by setting `itunes: true`. In the above example, the `itunes: true` option is used to demonstrate that the partial feed is returning a subset of episodes. By fetching additional iTunes data, we can compare the total number of episodes from the iTunes metadata with the number of episodes returned in the partial feed.
### Pagination
Pagination allows you to control the number of episodes returned by the parser. It lets you define the starting point and the limit for fetching the episodes. When parsing a partial feed with `requestSize` set, be aware that the episodes you request may not be in the feed.
```javascript
import { podcastXmlParser } from "podcast-xml-parser";
const config = { start: 0, limit: 10 }; // Last 10 episodes
const { episodes } = await podcastXmlParser(1438054347, config); // From an iTunes ID
console.log(episodes.length); // 10
```
## TypeScript
```typescript
import { podcastXmlParser, Podcast, Episode, Itunes } from "podcast-xml-parser";
const url = new URL("https://feeds.simplecast.com/dHoohVNH"); // From a URL
const { podcast }: { podcast: Podcast } = await podcastXmlParser(url);
console.log(podcast.title); // "Conan O’Brien Needs A Friend"
```
### Types
The library defines the following custom types that can be used in your code:
#### 1. `Podcast`
```typescript
interface Podcast {
copyright: string;
contentEncoded: string;
description: string;
feedUrl: string;
image: {
link: string;
title: string;
url: string;
};
itunesAuthor: string;
itunesCategory: string;
itunesExplicit: boolean;
itunesImage: string;
itunesOwner: {
name: string;
email: string;
};
itunesSubtitle: string;
itunesSummary: string;
itunesType: string;
language: string;
link: string;
title: string;
}
```
#### 2. `Episode`
```typescript
interface Episode {
author: string;
contentEncoded: string;
description: string;
enclosure: {
url: string;
type: string;
};
guid: string;
itunesAuthor: string;
itunesDuration: number;
itunesEpisode: number | null;
itunesEpisodeType: string;
itunesExplicit: boolean;
itunesImage: string;
itunesSeason: number | null;
itunesSubtitle: string;
itunesSummary: string;
itunesTitle: string;
link: string;
pubDate: string;
title: string;
}
```
#### 3. `Config`
```typescript
interface Config {
start?: number;
limit?: number;
requestHeaders?: Record<string, string>;
requestSize?: number;
itunes?: boolean;
}
```
#### 4. `Itunes`
**Note**: The `Itunes` type interface reflects the current structure of the iTunes API response. However, this structure is subject to change without notice, and fields may be absent in some responses. Developers should implement appropriate error handling to accommodate potential changes and missing fields in the iTunes data.
```typescript
interface Itunes {
wrapperType?: string;
kind?: string;
collectionId?: number;
trackId?: number;
artistName?: string;
collectionName?: string;
trackName?: string;
collectionCensoredName?: string;
trackCensoredName?: string;
collectionViewUrl?: string;
feedUrl?: string;
trackViewUrl?: string;
artworkUrl30?: string;
artworkUrl60?: string;
artworkUrl100?: string;
artworkUrl600?: string;
collectionPrice?: number;
trackPrice?: number;
trackRentalPrice?: number;
collectionHdPrice?: number;
trackHdPrice?: number;
trackHdRentalPrice?: number;
releaseDate?: string;
collectionExplicitness?: string;
trackExplicitness?: string;
trackCount?: number;
country?: string;
currency?: string;
primaryGenreName?: string;
contentAdvisoryRating?: string;
genreIds?: string[];
genres?: string[];
}
```
## Running Tests
To run the test suite, execute the following command:
```bash
npm test
# or
yarn test
```
## Contribution
Contributions to `podcast-xml-parser` are welcome! If you find any bugs, have feature requests, or want to improve the library, feel free to open an issue or submit a pull request.
## License
This project is licensed under the MIT License.
| 🎙 Parse podcast feeds in browsers, React Native, or Node.js environments. | javascript,node,parse,podcast,typescript,xml | 2023-08-08T09:08:17Z | 2024-05-14T23:40:08Z | null | 1 | 7 | 283 | 1 | 2 | 5 | null | MIT | TypeScript |
MozamelJawad/ToDoList_Review | main |
## To Do List Project Review
<a name="readme-top"></a>
<!-- TABLE OF CONTENTS -->
# 📗 Table of Contents
- [📖 About the Project](#about-project)
- [🛠 Built With](#built-with)
- [Tech Stack](#tech-stack)
- [Live Demo](#live-demo)
- [Key Features](#key-features)
- [💻 Getting Started](#getting-started)
- [Setup](#setup)
- [Prerequisites](#prerequisites)
- [Install](#install)
- [Usage](#usage)
- [Run tests](#run-tests)
- [Deployment](#deployment)
- [👥 Authors](#authors)
- [🔭 Future Features](#future-features)
- [🤝 Contributing](#contributing)
- [⭐️ Show your support](#support)
- [🙏 Acknowledgements](#acknowledgements)
- [📝 License](#license)
<!-- PROJECT DESCRIPTION -->
# 📖 ToDoList <a name="about-project"></a>
**ToDoList** is a learning project that builds in HTML, CSS, and Javascript and uses webpack to bundle Javascript; in this project, proper ES6 syntax is also implemented.
The **ToDo List** interactive application helps you to add your functionalities; in the case of completion, you can mark it as complete, and if you want to delete it, it will be completely deleted from the list and local storage.
## 🛠 Built With <a name="built-with"></a>
### Tech Stack <a name="tech-stack"></a>
<ul>
<li>Linters</li>
<li>Webpack</li>
<li>HTML</li>
<li>CSS3</li>
<li>JS (ES6 synthax)</li>
</ul>
## 🚀 Live Demo <a name="live-demo"></a>
- [Live Demo](https://mozameljawad.github.io/ToDoList/dist/)
##
<!-- Features -->
### Key Features <a name="key-features"></a>
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- GETTING STARTED -->
## 💻 Getting Started <a name="getting-started"></a>
### Setup
Clone this repository to your desired folder:
https://github.com/MozamelJawad/ToDoList
### Install
<ul>
<li>npm init -y </li>
<li>npm install webpack webpack-cli --save-dev</li>
<li>npm install --save-dev html-webpack-plugin</li>
<li>npm install webpack webpack-cli --save-dev</li>
<li>npm install --save-dev style-loader css-loader </li>
<li>npm install --save-dev webpack-dev-server</li>
<li>npm run build</li>
<li>npm start </li>
</ul>
### Usage
To run the project, execute the following command:
> npm install
### Run tests
> np start
### Deployment
Project can be deployed by using the gh-pages and other web platforms.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- AUTHORS -->
## 👥 Authors <a name="authors"></a>
👤 **Mozamel Jawad**
- GitHub: [@githubhandle](https://github.com/MozamelJawad)
- Twitter: [@twitterhandle](https://twitter.com/mozameljawad)
- LinkedIn: [LinkedIn](https://www.linkedin.com/in/mozamel-jawad-2b4421111/)
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- FUTURE FEATURES -->
## 🔭 Future Features <a name="future-features"></a>
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- CONTRIBUTING -->
## 🤝 Contributing <a name="contributing"></a>
Contributions, issues, and feature requests are welcome!
Feel free to check the [issues page](https://github.com/MozamelJawad/ToDoList/issues).
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- SUPPORT -->
## ⭐️ Show your support <a name="support"></a>
If you like this project, give a ⭐️
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- ACKNOWLEDGEMENTS -->
## 🙏 Acknowledgments <a name="acknowledgements"></a>
I would like to thank from Microverse
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- LICENSE -->
## 📝 License <a name="license"></a>
This project is [MIT](./LICENSE) licensed.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
| This repository is only created to review the To-Do list project | css,html,javascript,linter-config,webpack5 | 2023-07-24T17:21:41Z | 2023-07-25T12:09:06Z | null | 2 | 1 | 5 | 0 | 0 | 5 | null | MIT | JavaScript |
Alok-2002/Calculator_Wizard | main | # Calculator_Wizard
A simple calculator project made using HTML, CSS, and JavaScript.
## Live Demo
Check out the live demo [Calculator Wizard](https://calculator-Wizard.vercel.app).
## Description
The Calculator_Wizard is a web-based calculator that allows users to perform basic arithmetic operations in their web browser. It was created using HTML for the structure, CSS for the styling, and JavaScript for the interactive functionalities.
## Features
- Addition, subtraction, multiplication, and division operations.
- Clear button to reset the calculator.
- Keyboard support for number input and basic operators.
## Usage
1. Open the [Live demo](https://Calculator-Wizard.vercel.app) link in your web browser.
2. Use the mouse to click on the buttons to input numbers and perform calculations.
3. Alternatively, you can use your keyboard to input numbers and operators for calculations.
## Local Development
If you want to run the project locally and explore or make changes, follow these steps:
1. Clone the repository:
```bash
git clone https://github.com/alok-2002/Calculator_Wizard.git
```
2. Navigate to the project directory:
```bash
cd Calculator_Wizard
```
3. Open the `index.html` file in your preferred web browser.
## Technologies Used
- HTML
- CSS
- JavaScript
## Deployment
The project is deployed using Vercel. Vercel is a cloud platform for static sites and serverless functions that makes it easy to deploy and manage your applications.
## License
This project is licensed under the [MIT License](LICENSE).
## Acknowledgments
- This project was inspired by my love for web development and desire to create a useful tool for calculations.
- Special thanks to Vercel for providing an platform for deploying web projects.
| A simple calculator project made using HTML, CSS, and JavaScript. | alok,alok-2002,alok-sharma,calculator,css,deployment,git,github,html,html-css-javascript | 2023-07-26T14:14:38Z | 2023-07-30T14:42:47Z | null | 1 | 0 | 16 | 0 | 0 | 4 | null | MIT | HTML |
Web3Jharkhand/web3jh | main | <h1> Web3Jharkhand Official Website 🚀 </h1>
<div align="left">
<a href="https://github.com/Web3Jharkhand/web3jh/"><img src="https://sloc.xyz/github/Web3Jharkhand/web3jh" alt="LOC"/></a>
<a href="https://github.com/Web3Jharkhand/web3jh/"><img src="https://img.shields.io/github/stars/Web3Jharkhand/web3jh" alt="Stars Badge"/></a>
<a href="https://github.com/Web3Jharkhand/web3jh/network/members"><img src="https://img.shields.io/github/forks/Web3Jharkhand/web3jh" alt="Forks Badge"/></a>
<a href="https://github.com/Web3Jharkhand/web3jh/graphs/contributors"><img alt="GitHub contributors" src="https://img.shields.io/github/contributors/Web3Jharkhand/web3jh?color=2b9348"></a>
</div>
<h3> 👉 How to Contribute </h3>
Steps to follow:
1. **Research & Planning**
- Before you start working on the project, first visit our website at *https://web3jharkhand.github.io/web3jh/*
- Go through the website thoroughly 10-20 times and find out that particular section that you think might require some improvement or bug fixes.
- Verify if someone is already working on that by going through the issues currently opened at *https://github.com/Web3Jharkhand/web3jh/issues*
2. **Assignment**
- If there's already an "issue" opened for that particular task, then assign it to yourself to start working on it.
- If there is no "issue" currently raised for that task, then go to *https://github.com/Web3Jharkhand/web3jh/issues/new* and create one with appropriate "TITLE" & appropriate description explaining what you will be fixing or building any new.
3. **Prerequisites**
- To work on this project you require atleast a basic understanding of HTML, CSS & JavaScript.
- You will also require a basic understanding of React (A JS library) to work on this project.
4. **Setting up your Environment** (OPTIONAL)
- If qualify for the above prerequisites then feel free to follow the below steps to set up "Node.js" & "npm" if not already done.
- Download Node.js LTS installer as per your OS from *https://nodejs.org/en/download*
- Once it's installed then open "command prompt" and enter these commands respectively to verify if node & npm have been setup successfully `node --version` and `npm --version`
- In case it doesn't recognize then, you need to manually set the path. Google it to know how to create new environment variable or set the path.
5. **Code Setup**
- Star ⭐ the repo by clicking on the *"Starred"* button on the top right side of the screen.
- *"Fork"* this repo into your own GitHub account allowing you to work on a copy of it, thus allowing you to freely experiment with changes without affecting the original project.
- Clone this repository in your local system using the command `git clone` OR download it as a zip file.
- Once you have successfully downloaded it into your local system, open your preferred code editor terminal and run `npm install`
- To run it locally on your system for testing, make sure to first edit the 1st line of code of the file "package.json" to `"homepage": "."` and then run `npm start`
<br>
<h3> 👉 TECH STACK </h3>
<h3> Languages: </h3>
<div>
<img align="left" width="95px" src="https://img.shields.io/badge/-HTML5-13324B?logo=html5&Color=white&style=plastic" />
<img align="left" width="70px" src="https://img.shields.io/badge/-CSS-1572B6?logo=CSS3&Color=white&style=plastic" />
<img align="left" width="125px" src="https://img.shields.io/badge/-JavaScript-13324B?logo=javascript&Color=white&style=plastic" />
<img align="left" width="85px" src="https://img.shields.io/badge/-React-1572B6?logo=react&Color=white&style=plastic" />
</div>
<br>
<h3> Tools: </h3>
<div>
<img align="left" width="85px" src="https://img.shields.io/badge/-Figma-1572B6?logo=figma&Color=white&style=plastic" />
<img align="left" width="180px" src="https://img.shields.io/badge/-Visual Studio Code-1572B6?logo=visualstudiocode&Color=white&style=plastic" />
</div>
<br><br>
<h3> 👉 GLIMPSE OF WEBSITE </h3>
<h1 align=center> ⭐ OUR VALUABLE CONTRIBUTORS ⭐ </h1>
<p align="center">
<a href="https://github.com/Web3Jharkhand/web3jh/graphs/contributors">
<img src="https://contrib.rocks/image?repo=Web3Jharkhand/web3jh" />
</a>
</p>
<h2> 🔗 Connect with Us </h2>
[<img alt="Web3 Jharkhand | Mail" width="80px" src="https://img.shields.io/badge/-Gmail-000000?logo=gmail&Color=0A66C2&style=flat-square" />](mailto:web3jh@gmail.com)
[<img alt="Web3 Jharkhand | LinkedIn" width="100px" src="https://img.shields.io/badge/-LinkedIn-000000?logo=linkedin&Color=0A66C2&style=flat-square" />](https://www.linkedin.com/company/web3jh/)
[<img alt="Web3 Jharkhand | Instagram" width="100px" src="https://img.shields.io/badge/-Instagram-000000?logo=instagram&Color=0A66C2&style=flat-square" />](https://www.instagram.com/web3jh/)
[<img alt="Web3 Jharkhand | Twitter" width="92px" src="https://img.shields.io/badge/-Twitter-000000?logo=twitter&Color=0A66C2&style=flat-square" />](https://twitter.com/web3jh)
| Web3 Jharkhand Official Website | css,git,github-pages,html,javascript,npm,react | 2023-08-05T14:50:53Z | 2023-09-24T18:16:21Z | null | 3 | 4 | 38 | 1 | 3 | 4 | null | null | JavaScript |
vinay-code7/videocall-express | main | # Conference Video Call App
Welcome to the Conference Video Call App! This is a simple web application built using Express, Socket.IO, Peerjs, and EJS that allows users to create and join video conference calls.
## How to Use
- Visit the site at [videocall-express.onrender.com](https://videocall-express.onrender.com/)
- Simply enter a room ID that you want to create a new room.
- Tell your friends this room ID and they can join the same room.
## Features
- Create a new conference room using any room id you want.
- Join an existing conference room using the room ID.
- Real-time video and audio communication between participants in the same room.
- Secure and reliable communication.
- Simple and intuitive user interface for easy usage.
## Technologies Used
- Express: A fast, unopinionated, and minimalist web framework for Node.js.
- Socket.IO: A library that enables real-time, bidirectional, and event-based communication between the browser and the server.
- Peerjs: A library for WebRTC peer-to-peer communication.
- EJS: A simple and effective templating language to generate HTML markup with plain JavaScript.
## Demo
Yes, I literally gathered 4 devices to make the demo and the one with blurry video is actually my broken webcam. 😆. PS. Message me if you ever want to have conversation with me on this app. 😃
## Setup Locally
- Clone/download this repository to your local machine.
- Use `npm i` to install dependencies.
- Use `npm start` or `npm run dev` to start the server.
- Go to [localhost:5000](http://localhost:5000) to see the running app.
## Features I want to implement
- [x] Custom Room ID
- [x] Peer to Peer connection
- [x] Multiple Users
- [x] Simple UI
- [ ] Mute Audio / Hide Video
- [ ] Display names of users
# Contribution
Contributions are always welcome! If you find any issues with the application or want to add new features, please feel free to open an issue or submit a pull request.
# License
This project is licensed under the MIT License.
# Acknowledgments
Thanks to the developers of Express, Socket.IO, Peerjs, and EJS for their excellent libraries.
| A Conference Video Call web application made using ExpressJS and Socket.io | ejs,express,fun-project,javascript,socket-io,video-call,webrtc | 2023-07-30T18:48:08Z | 2023-08-02T21:02:18Z | null | 1 | 1 | 14 | 0 | 0 | 4 | null | MIT | JavaScript |
devmnl/Calculadora-de-bobinas | main | # Calculadora-de-bobinas
| Ferramenta de cálculos para o setor de embalagens flexíveis | empresas,ferramentas,javascript | 2023-08-01T13:54:44Z | 2023-08-05T07:19:20Z | null | 1 | 0 | 28 | 0 | 0 | 4 | null | null | CSS |
ux4g/ux4g-design-system-v1 | main | <p align="center" dir="auto">
<img style="height:auto; " alt="" src="https://miro.medium.com/v2/resize:fill:176:176/1*xumZgHQaB2V-7TRglungzQ.png" height="200" >
</p>
<h1>UX4G Design System</h1>
Our default branch is for development of our UX4G release.
<h2>Quick start</h2>
Several quick start options are available:
<ul>
<li><a href="https://doc.ux4g.gov.in/assets/UX4G@1.0.0.zip" >Download the latest release</a> </li>
</ul>
<ul>
<li>Clone the repo: <code>git clone https://github.com/ux4g/ux4g-design-system-v1.git</code> </li>
</ul>
Read the <a href="https://doc.ux4g.gov.in/">Getting started page </a> for information on the framework contents, templates, examples, and more.
<h2>What's included</h2>
Within the download you'll find the following directories and files, logically grouping common assets and providing both compiled and minified variations.
<details>
<summary>Download contents</summary>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto"><pre lang="text" class="notranslate"><code>ux4g/
├── css/
│ ├── ux4g-grid.css
│ ├── ux4g-grid.css.<span class="hljs-built_in">map</span>
│ ├── ux4g-grid.<span class="hljs-built_in">min</span>.css
│ ├── ux4g-grid.<span class="hljs-built_in">min</span>.css.<span class="hljs-built_in">map</span>
│ ├── ux4g-grid.rtl.css
│ ├── ux4g-grid.rtl.css.<span class="hljs-built_in">map</span>
│ ├── ux4g-grid.rtl.<span class="hljs-built_in">min</span>.css
│ ├── ux4g-grid.rtl.<span class="hljs-built_in">min</span>.css.<span class="hljs-built_in">map</span>
│ ├── ux4g-reboot.css
│ ├── ux4g-reboot.css.<span class="hljs-built_in">map</span>
│ ├── ux4g-reboot.<span class="hljs-built_in">min</span>.css
│ ├── ux4g-reboot.<span class="hljs-built_in">min</span>.css.<span class="hljs-built_in">map</span>
│ ├── ux4g-reboot.rtl.css
│ ├── ux4g-reboot.rtl.css.<span class="hljs-built_in">map</span>
│ ├── ux4g-reboot.rtl.<span class="hljs-built_in">min</span>.css
│ ├── ux4g-reboot.rtl.<span class="hljs-built_in">min</span>.css.<span class="hljs-built_in">map</span>
│ ├── ux4g-utilities.css
│ ├── ux4g-utilities.css.<span class="hljs-built_in">map</span>
│ ├── ux4g-utilities.<span class="hljs-built_in">min</span>.css
│ ├── ux4g-utilities.<span class="hljs-built_in">min</span>.css.<span class="hljs-built_in">map</span>
│ ├── ux4g-utilities.rtl.css
│ ├── ux4g-utilities.rtl.css.<span class="hljs-built_in">map</span>
│ ├── ux4g-utilities.rtl.<span class="hljs-built_in">min</span>.css
│ ├── ux4g-utilities.rtl.<span class="hljs-built_in">min</span>.css.<span class="hljs-built_in">map</span>
│ ├── ux4g.css
│ ├── ux4g.css.<span class="hljs-built_in">map</span>
│ ├── ux4g.<span class="hljs-built_in">min</span>.css
│ ├── ux4g.<span class="hljs-built_in">min</span>.css.<span class="hljs-built_in">map</span>
│ ├── ux4g.rtl.css
│ ├── ux4g.rtl.css.<span class="hljs-built_in">map</span>
│ ├── ux4g.rtl.<span class="hljs-built_in">min</span>.css
│ └── ux4g.rtl.<span class="hljs-built_in">min</span>.css.<span class="hljs-built_in">map</span>
└── js/
├── ux4g.bundle.js
├── ux4g.bundle.js.<span class="hljs-built_in">map</span>
├── ux4g.bundle.<span class="hljs-built_in">min</span>.js
├── ux4g.bundle.<span class="hljs-built_in">min</span>.js.<span class="hljs-built_in">map</span>
├── ux4g.esm.js
├── ux4g.esm.js.<span class="hljs-built_in">map</span>
├── ux4g.esm.<span class="hljs-built_in">min</span>.js
├── ux4g.esm.<span class="hljs-built_in">min</span>.js.<span class="hljs-built_in">map</span>
├── ux4g.js
├── ux4g.js.<span class="hljs-built_in">map</span>
├── ux4g.<span class="hljs-built_in">min</span>.js
└── ux4g.<span class="hljs-built_in">min</span>.js.<span class="hljs-built_in">map
</code></pre></div>
</details>
<p>We provide compiled CSS and JS (ux4g.*), as well as compiled and minified CSS and JS (ux4g.min.*). Source maps (ux4g.*.map) are available for use with certain browsers' developer tools. Bundled JS files (ux4g.bundle.js and minified ux4g.bundle.min.js) include <a href="https://popper.js.org/" target="_blank">Popper</a>.</p>
<h2>Documentation</h2>
<div class="table-responsive"><table class="table">
<thead>
<tr>
<th>Description</th>
<th>URL</th>
</tr>
</thead>
<tbody>
<tr>
<td>CSS</td>
<td><code>https://img1.digitallocker.gov.in/ux4g/UX4G@1.0.0/css/ux4g-min.css</code></td>
</tr>
<tr>
<td>JS</td>
<td><code>https://img1.digitallocker.gov.in/ux4g/UX4G@1.0.0/js/ux4g.min.js</code></td>
</tr>
</tbody>
</table></div>
<p>OR</p>
<h3>Compiled CSS and JS</h3>
<p>
Drop ready-to-use compiled code for <strong> UX4G v1.0.0 </strong> into the project by downloading it, which contains:
</p>
<ul class="un_order_list pl-30">
<li>CSS bundles that have been combined and compressed (see <a href="https://img1.digitallocker.gov.in/ux4g/UX4G@1.0.0/css/ux4g-min.css" target="_blank" rel="noopener noreferrer">CSS files comparison</a>)</li>
<li>JavaScript plugins that have been compiled and minified (see <a href="https://img1.digitallocker.gov.in/ux4g/UX4G@1.0.0/js/ux4g.min.js" target="_blank" rel="noopener noreferrer">JS files comparison</a>)</li></ul>
<p>This excludes any source files, documentation, or optional JavaScript dependencies like Popper.</p>
<a href="/assets/UX4G@1.0.0.zip" target="_blank" rel="noopener noreferrer" class="btn btn-outline-primary mb-100">Download</a>
<h2>Community</h2>
<p>Get updates on UX4G's development and chat with the project maintainers and community members.
</p>
<u>
<li>Follow <a href="https://twitter.com/ux_4g" target="_blank">@ux_4g on Twitter</a></li>
</u>
<u>
<li>Watch and subscribe <a href="https://www.youtube.com/@UX4G/about"target="_blank">UX4g Youtube channel</a></li>
</u>
<u>
<li>Read and subscribe <a href="https://medium.com/@ux4g.gov.in"target="_blank">The UX4g Blog</a></li>
</u>
<h2>Versioning</h2>
<p>For transparency into our release cycle and in striving to maintain backward compatibility, ux4g is maintained under the <a href="https://semver.org/" target="_blank">Semantic Versioning guidelines</a>. Sometimes we screw up, but we adhere to those rules whenever possible.</p>
<h2>Creators</h2>
U4GX
<a href="https://twitter.com/ux_4g" target="_blank">@ux_4g on Twitter</a>
<h2>Copyright and license</h2>
<p>Code and documentation copyright 2023. Docs released under <a href="https://creativecommons.org/licenses/by/3.0/">Creative Commons</a></p>
| The most widely used HTML, CSS, and JavaScript framework for creating websites that are mobile-first and responsive. | css3,html,javascript,php,css-framework,scss,sass-framework | 2023-08-07T12:52:02Z | 2023-08-18T07:37:46Z | 2023-08-08T06:35:53Z | 1 | 0 | 17 | 0 | 0 | 4 | null | null | PHP |
viniciusxv27/Site-Vai-Aonde-Capixaba | main | # Site Principal Vai Aonde Capixaba
## 🚀 Começando
Essas instruções permitirão que você obtenha uma cópia do projeto em operação na sua máquina local para fins de desenvolvimento e teste.
### 📋 Pré-requisitos
* [HTML5](https://pt.wikipedia.org/wiki/HTML5) - Usado para criação do Site
* [CSS3](https://pt.wikipedia.org/wiki/CSS3) - Usado para estilizar o Site
* [JavaScript](https://developer.mozilla.org/pt-BR/docs/Web/JavaScript) - Linguagem Usada para acessar a API
* [PHP](https://www.php.net/) - Linguagem Usada para envio de formulario
### 🔧 Instalação
Passo-a-passo que informa o que você deve executar para ter um ambiente de desenvolvimento em execução.
```
Baixe os arquivos disponiveis no repositório
```
```
Mova a pasta para o servidor
```
```
O projeto está pronto para ser testado
```
## 🛠️ Construído com
* [HTML5](https://pt.wikipedia.org/wiki/HTML5) - Usado para criação do Site
* [CSS3](https://pt.wikipedia.org/wiki/CSS3) - Usado para estilizar o Site
* [JavaScript](https://developer.mozilla.org/pt-BR/docs/Web/JavaScript) - Linguagem Usada para acessar a API
* [PHP](https://www.php.net/) - Linguagem Usada para envio de formulario
## 📌 Versão
Nós usamos [GitHub](https://github.com/) para controle de versão.
## ✒️ Autor
* **Desenvolvedor** - [Vinicius Costa](https://github.com/viniciusxv27)
---
⌨️ com ❤️ por [Vinicius Costa](https://gist.github.com/viniciusxv27) 😊
| this repository contains all the necessary files for the design of the main website of the "Vai Aonde Capixaba" system, uses HTML5, CSS3, Javascript and PHP technologies | css3,html5,javascript,php,capixaba,vaiaonde | 2023-07-30T19:51:27Z | 2023-08-16T03:08:14Z | null | 1 | 0 | 3 | 0 | 0 | 4 | null | null | CSS |
123pzy/chat-flower | master | # Chat万花筒
> 国内可以免费使用的ChatGPT网站，使用自己的token享受不限次使用权限！
## 项目介绍
Chat万花筒不仅仅是一个可以帮助程序员练手的前端项目，还是以 “**帮助大家在国内免费灵活地使用ChatGPT**” 为初心的工具网站。
页面：
| 网站页面 | 描述 |
| --------- | ------------------------------------------------------------ |
| 💻注册登录 | 用户名不超过6个字符，密码格式不限 |
| 🏡网站主页 | 包含导航栏、搜索框、类别按钮、问答场景选择等 |
| 💬问答界面 | 左侧切换场景按钮，右侧为主问答窗口，右下方输入问题，ChatGPT流式回复 |
| 📚个人信息 | 点击顶部导航栏头像，跳转个人信息编辑页面，支持更换头像，修改用户名、查看剩余次数等 |
| 🔍教程界面 | 点击顶部导航栏 “教程” 跳转教程界面（相信你无师自通🤭） |
| 🧲获取次数 | 点击顶部导航栏 “购买次数” ，加个人微信增加使用次数 |
主要功能：
| 网站主要功能 |
| ---------------------------- |
| 与ChatGPT进行问答 |
| 自定义问答环境 |
| 切换问答环境 |
| 个人信息编辑（头像、用户名） |
| 增加使用次数 |
| 使用个人Token不限次使用 |
| 灵活调整ChatGPT的回复随机性 |
| 一键换肤（深浅色主题切换） |
| ...... |
## 主页展示
主页
问答界面
更多页面......
## 项目由来
从去年年底开始，ChatGPT这类AI产品在国内大火，但是在国内使用ChatGPT受限，使用者不得不寻找代理，但是并不是每个场景下都有代理，所以为了满足即使在缺少代理的情况下也能使用ChatGPT带来的服务，就有了本网站的雏形。
今年五月底，我阅读了ChatGPT的官网文档，自己实现一个简单的调用ChatGPT的单页面：
<img src="https://files.mdnice.com/user/32447/61346641-1722-45d4-9dfc-1afe3c8845a8.png" alt="image-20230804095258063" style="zoom: 33%;" />
之后并不满足只有自己使用，开始把这个当成一个个人项目来开发，并部署到国外的服务器，最终实现了国内任意用户，注册登录本网站即可使用ChatGPT的效果。
## 体验地址
[http://www.dapanna.cn:3000/](http://www.dapanna.cn:3000/)
| 国内可以免费使用的ChatGPT网站，使用自己的token享受不限次使用权限！ | vue3,chatgpt,css,html,javascript,koa,mysql,nodejs | 2023-08-02T13:49:10Z | 2023-08-26T09:25:14Z | null | 1 | 0 | 5 | 0 | 0 | 4 | null | null | Vue |
bestian/edu-lang | master | # 教育元語言 edu-lang
> 一種專門為了教育方式或學習方法分享而設計的[Markdown](https://markdown.tw/)之子語言。例如：「步驟」(一種固定格式的小階梯說明文)
> meta languages for edu( a set of sublanguage of [Markdown](https://en.wikipedia.org/wiki/Markdown) ), e.x. step
# 新手上路
0. 請先看[簡報頁](https://docs.google.com/presentation/d/1xtSwUsW4AI6fDaaFOLIFo-9NSxIbJ8Lws_w12D05ZpY/edit?usp=sharing)
1. 請先看[共筆區(Wiki)](https://github.com/bestian/edu-lang/wiki)的首頁
2. 錯誤回報與功能請求，請上[議題區(issues)](https://github.com/bestian/edu-lang/issues)
3. 若您還沒有Gtihub帳號，請[申請一個](https://git-scm.com/book/zh-tw/v2/GitHub-%E5%BB%BA%E7%AB%8B%E5%B8%B3%E6%88%B6%E5%8F%8A%E8%A8%AD%E5%AE%9A)
4. 若您還不會[Markdown](https://markdown.tw/)，沒有關係，它很簡單，至少比html簡單。請看此頁[Markdown文法說明](https://markdown.tw/)，或是此[Markdown範本集](https://hackmd.io/@eMP9zQQ0Qt6I8Uqp2Vqy6w/SyiOheL5N/%2FBVqowKshRH246Q7UDyodFA?type=book)謝謝。
6. 喜歡本專案的話，請記得幫忙訂閱(右上角的watch)和打星(右上角的star)集氣喔，謝謝！
# 開發環境
1. [Node.js](https://nodejs.org/zh-tw/download?ref=peppedotnet.it)
2. [Mocha](https://mochajs.org/)
3. google slide
4. 足夠的血糖和熱情❤️🔥
##
1. 收集並開發一些在教育領域常用的函式以及剖析器等等，從簡單的countAge到複雜的countStep, countTable, countTree, countClimbingStones等等
2. 為開源共學島提供基礎建設
3. 目標是打包到npm 想讓想用的專案都可以用
## 緣起(Idea)
一般來說，從入門到進階都會有一個小階梯，這稱為小階梯教學法。
如何把這個階梯表達出來，讓人很容易地可以編輯、很容易地看懂，這就是工程師要做的事情。
因為要表達小階梯，用演講、短文、YouTube這些方法都不是很有效率的。
有鑒於之前的[https://beta.hackfoldr.org/](https://github.com/hackfoldr/hackfoldr-2.0-forkme/blob/master/docs/Hosting%20your%20own%20Hackfoldr%202.0%20zh-tw.md) 對一般使用者還是太困難。
在他最後嘗試表達階梯的[Goban](http://goban.bestian.tw)，介面和表述的方式仍然太複雜，且一般人沒有動機網上分享東西。
看起來一個更簡單的語言表達方式是必要的。
他應該屬於Markdown的子類。
## 應用(Application)
* [Hackstep](https://github.com/3dw/hackstep) 開發中...
# 測試和發佈
## 測試
```mocha test```
## 發佈
1. 先增加packge.json裡的版本號
```npm publish```
| 一種專門為了教育方式或學習方法分享而設計的Markdown之子語言。例如：「步驟」(一種固定格式的小階梯說明文) meta languages for edu( a set of sublanguage of Markdown ), e.x. step | education,javascript,nodejs | 2023-07-31T22:50:58Z | 2023-09-19T02:27:59Z | null | 4 | 0 | 50 | 5 | 0 | 4 | null | null | JavaScript |
Engineervinay/threads-clone | main | # Clone of Threads app by Instagram
https://github.com/Engineervinay/threads-clone/assets/29520476/93e01bd9-820c-43aa-91d7-fcf9699a8eb2
## Getting Started with Create React App
This project was bootstrapped with [Create React App](https://github.com/facebook/create-react-app).
## Available Scripts
In the project directory, you can run:
## first install json-server
### use `json-server --watch db.json` to start server
### `npm start`
Runs the app in the development mode.\
Open [http://localhost:3000](http://localhost:3000) to view it in your browser.
The page will reload when you make changes.\
You may also see any lint errors in the console.
### Deployment
| Threads Clone | beginner,beginner-friendly,css,good-first-issue,html,javascript,reactjs,react-project | 2023-08-03T15:22:20Z | 2023-09-11T05:52:57Z | null | 2 | 2 | 33 | 2 | 2 | 4 | null | null | JavaScript |
elliezub/cat-generator | main | # Cat Generator
This project is a simple random cat GIF generator with a text overlay feature. It allows you to fetch random cat GIFs from a public API and then add custom text overlays to them, all built with React and Vite for speed and performance.
<img width="717" alt="Screen Shot 2023-07-26 at 11 58 42 PM" src="https://github.com/elliezub/cat-generator/assets/112726692/c072d728-6404-43d7-a3f3-e9859874ff19">
## Features
- Fetches a random cat GIF
- Add custom text overlay on the GIF
- Built with React for component-based architecture
- Vite for faster and leaner development experience
## Environment Variables
To run this project, you will need to add the following environment variables to your .env.local file
`VITE_APP_CAT_API_KEY`
And request an API key from https://thecatapi.com/
## Run Locally
Clone the project
```bash
git clone https://link-to-project
```
Go to the project directory
```bash
cd cat-generator
```
Install dependencies
```bash
npm install
```
Start the server
```bash
npm run dev
```
## Contributing
Contributions are always welcome!
## Credits
- Cat GIFs provided by the CatAPI.
Happy coding! 🐱🎉
| A cat generator made with React. | cat,javascript,meme-generator,react,reactjs,scrimba,vite | 2023-07-27T04:13:17Z | 2023-07-28T03:53:12Z | null | 1 | 1 | 9 | 1 | 2 | 4 | null | null | JavaScript |
MatanYadaev/eslint-plugin-testing | main | # eslint-plugin-testing
[](https://www.npmjs.com/package/eslint-plugin-testing)
[](https://github.com/MatanYadaev/eslint-plugin-testing/actions/workflows/ci.yaml)
ESLint plugin for testing.
## Installation
1. First, install [ESLint](https://eslint.org/):
```sh
npm install --save-dev eslint
```
2. Next, install `eslint-plugin-testing`:
```sh
npm install --save-dev eslint-plugin-testing
```
## Usage
Add `testing` to the plugins section of your `.eslintrc` configuration file:
```json
{
"plugins": ["testing"]
}
```
Then configure the rules you want to use under the rules section.
```json
{
"rules": {
"testing/aaa-comments": "error"
}
}
```
### Recommended
To use the recommended configuration, extend it in your `.eslintrc` file:
```json
{
"extends": ["plugin:testing/recommended"]
}
```
All recommend rules will be set to error by default. You can however disable some rules by setting turning them `off` in your `.eslintrc` file or by setting them to `warn` in your `.eslintrc`.
### All
To use the all configuration, extend it in your `.eslintrc` file:
```json
{
"extends": ["plugin:testing/all"]
}
```
## Rules
<!-- begin auto-generated rules list -->
💼 Configurations enabled in.\
⚠️ Configurations set to warn in.\
🌐 Set in the `all` configuration.\
✅ Set in the `recommended` configuration.
| Name | Description | 💼 | ⚠️ |
| :----------------------------------------- | :------------------- | :- | :- |
| [aaa-comments](docs/rules/aaa-comments.md) | Enforce AAA comments | ✅ | 🌐 |
<!-- end auto-generated rules list -->
## Licence
[MIT](https://github.com/MatanYadaev/eslint-plugin-testing/blob/main/LICENSE)
Copyright © 2023-present, Matan Yadaev
| ESLint plugin for testing. | best-practices,eslint,eslint-plugin,testing,eslint-plugin-testing,test-best-practices,javascript,nodejs | 2023-08-04T22:12:06Z | 2023-09-02T14:28:39Z | 2023-08-16T22:04:14Z | 1 | 2 | 30 | 5 | 0 | 4 | null | MIT | TypeScript |
masterujjval/Postgres_Authentication | main | # Register-Login-Update website
## About
Login-form-validation is a simple website that can run locally on any platform.
The user can register and then log in then land on the greeting page, it will store data on Postgresql locally to validate the registered users during the login process.
Postgresql for database, express for fetch, and post and node have been used to create this project.
---
### Update your password
The password can be updated with the registered email. Enter your registered email and then enter a new password after successfully updating the password it will redirect the user to the login page. Here, enter the email and the newly updated password and then the user can successfully log in.
---
## Prerequisite to run the website and server
* Postgresql
* NodeJs
* Knex.js
* To install Postgresql watch these tutorials for
* [windows](https://www.youtube.com/watch?v=0n41UTkOBb0)
* [ubuntu](https://www.youtube.com/watch?v=tducLYZzElo&t=329shttps://www.youtube.com/watch?v=tducLYZzElo&t=329s)
## Changes to be made after setup up the environment
Now to create a database to store registration and then for validation, we have to first create a database.
After, successfully installing Postgresql made some changes:-
Change the password and enter your password which was entered while creating a server with username ***postgres***.
---
Open the folder in vs code where you have cloned the project and follow the below steps to create a database:
***For Linux***
```shell
sudo -i -u postgres
```
Now create a database and name it 'loginform1'
```
createdb loginform
```
Now, switch to loginform1 database to create table
```
psql -d loginform1
```
Now copy the below lines to create a table to register users
```
CREATE TABLE users (id serial not null primary key, name varchar(255) not null, email varchar(255) not null unique, password varchar(255) not null);
```
run : ```SELECT * FROM users;``` to check whether the table is created or not.
Now you can run the project on your Linux.
---
***For Windows***
run: ```psql -U postgres```
then enter the password you have entered while creating a server with username ```postgres```
Create database: ```CREATE DATABASE loginform1```
switch to database: ```\c loginform1```
then copy the same command for creating a table:
```
CREATE TABLE users (id serial not null primary key, name varchar(255) not null, email varchar(255) not null unique, password varchar(255) not null);
```
Execute ```npm start``` in the vs code terminal to run the server.
Update.js file does not have any role in running all the files it is just to understand the update query. It can be run using node update.js in the terminal separately.
| User Authentication using Postgres as Database | css,git,javascript,js,minor-project,project | 2023-07-29T10:39:44Z | 2023-08-31T19:09:47Z | null | 1 | 0 | 29 | 0 | 0 | 4 | null | null | JavaScript |
KevyDev/portfolioV1 | master | null | My own portfolio using ReactJS. | css,html,javascript,nodejs,portfolio,portfolio-website,reactjs,sass | 2023-08-01T00:05:12Z | 2024-03-26T05:37:57Z | null | 1 | 6 | 27 | 0 | 0 | 4 | null | null | JavaScript |
dhruvabhat24/Java-Script | main | # Java-Script Code
1. Introduction
2. Difference between var let and const
3. Variables
4. Primitive and Non-Primitive(object) Datatypes
5. Operators and Expresssions in Java Script
6. Conditional Expression
7. For Loop
8. While Loop
9. Taking user input
# Practice code
1. Practice 1
2. Practice 2
| Javascript learnings | javascript,js,vscode | 2023-08-02T15:35:13Z | 2023-10-13T13:56:54Z | null | 1 | 2 | 40 | 0 | 0 | 4 | null | null | JavaScript |
yesworld/tutorial-dnd-animals | main | # Уроки как создать чистую ООП архитектуру для детской игры. / Lessons on how to create a pure OOP architecture for a children's game.
Детская интерактивная пазл игра с животными на ts (TypeScript), написанная с целью обучения, где мы попытаемся разбить [портянку старого кода](https://github.com/yesworld/tutorial-dnd-animals/commit/e74b428898f3da415e3d49b2497f80c56ee217b1#diff-4fab5baaca5c14d2de62d8d2fceef376ddddcc8e9509d86cfa5643f51b89ce3d) и создать свою **Чистую архитектуру** проекта, придерживаясь ООП стиля программирования с использованием паттернов.
We are developing an interactive game of puzzles for children with animals using Typescript. We will do a [refactor of the old code](https://github.com/yesworld/tutorial-dnd-animals/commit/e74b428898f3da415e3d49b2497f80c56ee217b1#diff-4fab5baaca5c14d2de62d8d2fceef376ddddcc8e9509d86cfa5643f51b89ce3d) and try to write with pure architecture. Where we will use the design of the pattern.
Сложность урока/difficulty of the lesson: :full_moon: :full_moon: :full_moon: :full_moon: :last_quarter_moon: (Очень сложно/Very hard)
<div dir="rtl">Image by <a href="https://www.freepik.com/free-vector/world-animal-day-flat-design-background_31240982.htm#&position=0&from_view=search&track=ais">Freepik</a></div>
## Список уроков на ютубе
- Урок 0: Подготовка проекта. Установка Vite, Prettier и Konva.<br>
:tv: [YouTube](https://www.youtube.com/watch?v=HO6wBG8FFqo)
- Урок 1: SVG нарезка и содание отдельных файлов c животными. Подготовка файла источника **sources** с набором координат.<br>
:tv: [YouTube](https://www.youtube.com/watch?v=k87xvt_7WcM) :octocat: [git-branch: tutorial-01](https://github.com/yesworld/tutorial-dnd-animals/tree/tutorial1-add-svg-animals-to-project)
- Урок 2: Создание ImageLoaderService по загрузке изображений. Добавление типов для TS.<br>
:tv: [YouTube](https://www.youtube.com/watch?v=rzPTPMg2E30&list=PLMo7VyNbwQJGgWBYHPTDysdNg1UiBXXMT&index=3) :octocat: [git-branch: tutorial2-create-image-loader-service](https://github.com/yesworld/tutorial-dnd-animals/tree/tutorial2-create-image-loder-service)
- Урок 3: Применяем пораждающий паттерн Билдер (Builder). Приводим проект к ООП стилю.<br>
:tv: [YouTube](https://www.youtube.com/watch?v=kjj_4czV--c&list=PLMo7VyNbwQJGgWBYHPTDysdNg1UiBXXMT&index=4) :octocat: [git-branch: tutorial3-create-game-builder](https://github.com/yesworld/tutorial-dnd-animals/tree/tutorial3-create-game-builder)
- Урок 4: Применяем пораждающий паттерн Фабрика (Simple Factory). Делаем небольшой рефакторинг.<br>
:tv: [YouTube](https://youtu.be/Npjy5hL6ppA&list=PLMo7VyNbwQJGgWBYHPTDysdNg1UiBXXMT&index=5) :octocat: [git-branch: tutorial4-create-konva-factory](https://github.com/yesworld/tutorial-dnd-animals/tree/tutorial4-create-konva-factory)
- Урок 5: Применяем анти паттерн Одиночка (Singleton).<br>
:tv: [YouTube](https://www.youtube.com/watch?v=T1l9GX3thv8&list=PLMo7VyNbwQJGgWBYHPTDysdNg1UiBXXMT&index=6) :octocat: [git-branch: tutorial5-create-pattern-singleton](https://github.com/yesworld/tutorial-dnd-animals/tree/tutorial5-create-pattern-singleton)
- Урок 6: Плюсы/минусы Синглитона в TypeScript. Создаем сервис для работе с размерами игры в ООП стиле.<br>
:tv: [YouTube](https://www.youtube.com/watch?v=hEdUgYRE2KM&list=PLMo7VyNbwQJGgWBYHPTDysdNg1UiBXXMT&index=7) :octocat: [git-branch: tutorial06-create-canvas-size-service](https://github.com/yesworld/tutorial-dnd-animals/tree/tutorial06-create-canvas-size-service)
- Урок 7: Применим SRP - принцип единой ответственности в TypeScript (SOLID).<br>
:tv: [YouTube](https://www.youtube.com/watch?v=OHxE1NKnPJc&list=PLMo7VyNbwQJGgWBYHPTDysdNg1UiBXXMT&index=8) :octocat: [git-branch: tutorial07-srp-animal-manager](https://github.com/yesworld/tutorial-dnd-animals/tree/tutorial07-srp-animal-manager)
- Урок 8: Живой пример поведенческого паттерна Наблюдатель (Observer) на TypeScript / JavaScript.<br>
:tv: [YouTube](https://www.youtube.com/watch?v=51Og538pXcw&list=PLMo7VyNbwQJGgWBYHPTDysdNg1UiBXXMT&index=9) :octocat: [git-branch: tutorial08-animal-observer](https://github.com/yesworld/tutorial-dnd-animals/tree/tutorial08-animal-observer)
- Урок 9: Создаем интерфейс для работы с игрой и добавим canvas confetti в callback завершения игры.<br>
:tv: [YouTube](https://www.youtube.com/watch?v=cl5BluRPn9U&list=PLMo7VyNbwQJGgWBYHPTDysdNg1UiBXXMT&index=10) :octocat: [git-branch: tutorial09-create-api-game-add-confetti-to-game](https://github.com/yesworld/tutorial-dnd-animals/tree/tutorial09-create-api-game-add-confetti-to-game)
- Урок 10 CI/CD: Build и Deploy нашей игры на TS для публикации в Git Pages при помощи GitHub Actions.<br>
:tv: [YouTube](https://www.youtube.com/watch?v=6duJm33Peag&list=PLMo7VyNbwQJGgWBYHPTDysdNg1UiBXXMT&index=11) :octocat: [commit: add deploy](https://github.com/yesworld/tutorial-dnd-animals/commit/08a92af9fac1d44a2ec8dca6c0369c6134c77ae3)
## Тот кто смог :)
- 🏆 https://github.com/davidbayra/game-puzzle-animals / 🕹 [Play](https://davidbayra.github.io/game-puzzle-animals/)
- 🏆 https://github.com/karfagen86/tutorial-dnd-animals-v2 / 🕹 [Play](https://karfagen86.github.io/tutorial-dnd-animals-v2/)
## Как ты можешь помочь проекту?
- ⭐️ Поставь звезду проекту **tutorial-dnd-animals** (справа наверху этой страницы).
- :tv: Подпишись на [канал](https://www.youtube.com/channel/UCRWYGOCWalOGOXnzqJd2MbQ).
- 💬 Оставь комментарий под видео.
- 👍 Воткни свой царский лайк.
### На кофе:
- ☕️ [boosty](https://boosty.to/dev_yesworld)
- ☕️ [donationalerts](https://www.donationalerts.com/r/dev_yesworld)
| A children's interactive puzzle game with animals, written for the purpose of learning TypeScript / JS and knowledge of OOP in the front end. We take a simple old game code and refactor everything with a clean architecture using design patterns. | konvajs,prettier,typescript,vite,gamedev,oop,javascript,patterns,solid,game | 2023-07-28T07:28:39Z | 2024-04-16T07:00:11Z | null | 1 | 21 | 73 | 0 | 1 | 4 | null | null | TypeScript |
Jhonatan2022/JS-REACT-NODE | main | # Javascript-React-Node
[](https://jhonatan2022.github.io/JS-REACT-NODE/Frontend/Api-rest-JS/avanzado-api)
[](https://jhonatan2022.github.io/JS-REACT-NODE/Frontend/ReactJS/react-patrones-render/build) | null | emascript,javascript,javascript-engine,nodejs,poo,react,server | 2023-08-02T14:03:06Z | 2023-09-30T22:45:36Z | null | 1 | 92 | 200 | 0 | 0 | 4 | null | MIT | JavaScript |
Vikramkaza/Dash_God | main |
# Project Title
Dashboard for Advanced CCTV analytics app - GOD's EYE
## Appendix
This is a data viewing dashboard through which the data from the flask CCTV analytics app is fetched and shown in an easy to understand manner.
The dashboard has mainly three pages,
Sign-Up page
Login page
Analytics page
## Sign-up page
In this page not every user can sign up, this page is encrypted using AES encryption. So, only the authorities who have the auth key can sigh-up and access the portal. The sign up page contains a form which has the following feilds user_name, password and confirm password.
## Login Page
The usual login page which is linked with the data base of the signup page using flask.
## Dashboard
This dashboard page contains the major info of CCTV analyics. The table consits of the following coloumns Camera-name, date, time, location of the crime, confidence level and the detected object.
This data updates is real time with near no visible delay less than 3 seconds.
## Analytics Page
This page takes the data from the dashboard table and shows the same data in interactive graphs which can be used for further investigation/analysis. These graphs are easy to understand and no prerequisite is required for anyone to understand these graphs.
## Screenshots
**This is the login page of the Dashboard.**
**This is the signup page of the Dashboard.**
**This is the main dasboard page.**
**This is the analytics page where the data from the table is shown in interactive graphs.**
| This is a Dashboard for a Andavced CCTV analytics application. It shows the data which is fetched from the flask app, in a easy to understand table and graphs. | bootstrap,css,flask,html,javascript,plotly,python3 | 2023-08-08T09:07:14Z | 2023-08-11T10:10:23Z | null | 4 | 0 | 14 | 0 | 0 | 4 | null | null | HTML |
Rj1221/CODSOFT | main | # CODSOFT - Internship Repository
🌐 WebDev Internship Repository: A collection of my web development projects and code samples created during my internship. Exploring frontend and backend technologies to build modern, responsive, and dynamic web applications. Join me on my coding journey and let's create the web of tomorrow! 🚀 #WebDevelopment #Internship #CodeSamples"
## Table of Contents
**Landing Page**
- [Task 1](https://github.com/Rj1221/CODSOFT/tree/main/LandingPage)
**Calculator**
- [Task 2](https://github.com/Rj1221/CODSOFT/tree/main/Calculator)
**Portfolio**
- [Task 3](https://github.com/Rj1221/CODSOFT/tree/main/Portfolio)
---
## License
This project is licensed under the [MIT License](LICENSE), which means you're free to use, modify, and distribute the code as long as you include the original copyright and disclaimers. Refer to the LICENSE file for more details.
**[⬆ Back to Top](#table-of-contents)**
| 🌐 WebDev Internship Repository: A collection of my web development projects and code samples created during my internship. Exploring frontend and backend technologies to build modern, responsive, and dynamic web applications. Join me on my coding journey and let's create the web of tomorrow! 🚀 #WebDevelopment #Internship #CodeSamples" | css,html,html-css-javascript,javascript,webtechnologies,webtechnology | 2023-07-30T11:53:43Z | 2023-08-11T01:20:10Z | null | 1 | 0 | 26 | 0 | 2 | 4 | null | MIT | HTML |
TiffanyChan614/Vocabulary-Builder | main | # Vocabulary Builder
## Table of Contents
- [Overview](#overview)
- [Description](#description)
- [Motivation](#motivation)
- [Problem Statement](#problem-statement)
- [Video Demo](#video-demo)
- [Mobile Demo](#mobile-demo)
- [Live Demo](#live-demo)
- [Getting Started](#getting-started)
- [Built with](#built-with)
- [Dependencies](#dependencies)
- [Features](#features)
- [Key Features](#key-features)
- [Future Features](#future-features)
- [API](#api)
- [License](#license)
## Overview
### Description
This is a Vocabulary Builder app that is built with React, Tailwind CSS, and HTML. It is designed to enhance user vocabulary in a seamless and engaging way. This app is built as a personal project to practice React and Tailwind CSS. It is currently a front-end only app using local storage to store the data but will be updated to a full-stack app that use MongoDB in the future.
### Motivation
The inspiration behind this project came from my own experiences as someone whose first language is not English and also my husband, who is currently learning English. We both experienced the difficulty in expanding our English vocabulary due to the lack of engaging and customizable tools available. Hence, I felt compelled to create an vocabulary app that offers a built-in dictionary but also grants user the ability to customize their learning journey.
### Problem Statement
Existing vocabulary-building tools often follow a rigid, one-size-fits-all approach, offering a predefined list of words that may not suit learners of various proficiency levels. Additionally, these tools typically lack dynamic features for customization, particularly the ability for users to associate images with words. This feature is especially valuable for individuals with dyslexia, for whom visual aids play a crucial role in learning.
Furthermore, conventional tools struggle to deliver engaging learning experiences like flashcards or quizzes tailored to vocabulary acquisition. While there are plenty of flashcard apps available, they often lack a dedicated built-in dictionary for seamless learning.
### Video Demo
https://github.com/TiffanyChan614/Vocabulary-Builder/assets/68774129/e029515f-b6e4-48aa-a5c2-5ad8f9eed987
### Mobile Demo
<img width="307" alt="home" src="https://github.com/TiffanyChan614/Vocabulary-Builder/assets/68774129/74efd71c-5622-445e-87b2-77beafbda129">
<img width="312" alt="search" src="https://github.com/TiffanyChan614/Vocabulary-Builder/assets/68774129/836cff49-fd2d-4338-8aad-b18d334a2b26">
<img width="310" alt="journal" src="https://github.com/TiffanyChan614/Vocabulary-Builder/assets/68774129/448c9da0-378b-4953-bdb0-eb30fc8c12ac">
<img width="311" alt="flashcards" src="https://github.com/TiffanyChan614/Vocabulary-Builder/assets/68774129/0e797a7d-3549-41e6-a556-1d9faaba35af">
<img width="312" alt="quiz" src="https://github.com/TiffanyChan614/Vocabulary-Builder/assets/68774129/19243ce3-79b5-41b8-87d6-4f284224454d">
### Live Demo
Since this app is using the freemium plan of WordsAPI, the number of requests per day is limited. If you are interested in this app, please email me at tiffanychan1999614@gmail.com to get the live demo link.
## Getting Started
### Built with
- HTML 5
- React JS
- Figma
- Tailwind CSS
- React Router
- Redux
- REST API
- create-react-app
### Run Locally
Clone the project
```bash
git clone https://github.com/TiffanyChan614/Vocabulary-Builder.git
```
Go to the project directory
```bash
cd Vocabulary-Builder/vocabularybuilder
```
Install dependencies
```bash
npm install
```
Start the server
```bash
npm run start
```
### Dependencies
This project depends on the following packages:
- `classnames` (version ^2.3.2): A JavaScript utility for conditionally joining classNames together.
- `he` (version ^1.2.0): A robust HTML entity encoder/decoder.
- `react` (version ^18.2.0): A JavaScript library for building user interfaces.
- `react-dom` (version ^18.2.0): A package for working with the DOM in React applications.
### Development Dependencies
This project also has the following development dependencies:
- `@types/react` (version ^18.0.37): TypeScript definitions for the React library.
- `@types/react-dom` (version ^18.0.11): TypeScript definitions for the react-dom package.
- `@vitejs/plugin-react` (version ^4.0.0): A Vite plugin for React development.
- `eslint` (version ^8.38.0): A tool for identifying and reporting on patterns found in ECMAScript/JavaScript code.
- `eslint-plugin-react` (version ^7.32.2): An ESLint plugin for React-specific linting rules.
- `eslint-plugin-react-hooks` (version ^4.6.0): An ESLint plugin for enforcing rules of Hooks in React applications.
- `eslint-plugin-react-refresh` (version ^0.3.4): An ESLint plugin for react-refresh.
- `vite` (version ^4.4.2): A frontend tooling platform that provides faster and leaner development for modern web projects.
## Features
### Key Features
- **Built-in Dictionary**: Users can search for words directly within the application, providing quick access to definitions and information.
- **Dynamic Word Form**: Customize word information and add it to a personal journal for future review. This feature enables users to tailor the content to their learning preferences.
- **Image API Integration**: Utilizes a built-in image API to retrieve related images for visual association with words. Users can also upload their own images to associate with specific words.
- **Voice Pronunciation**: Provides voice pronunciation for words, allowing users to learn the correct pronunciation.
- **Word of the Day**: Displays a new word each day, allowing users to learn new words every day.
- **Part of Speech Filters**: Filter words based on their part of speech, allowing users to focus on specific categories for targeted learning.
- **Show Details**: Users can choose to show or hide word details, providing a clean and simple interface for learning.
- **Sort Journal Words**: Users have the ability to sort their journal words, providing an organized and efficient way to review and manage their vocabulary.
- **Persistent Filter, Show Details and Sort Settings**: Filter, show details, and sort settings persist across pages, ensuring that user preferences are maintained throughout their learning journey.
- **Review Modes**:
- **Flashcards**: Engage in a flashcard-based review mode for efficient and effective learning.
- **Quiz Mode**: Test your knowledge with a dynamic quiz mode that includes various question types.
- **Smart Review Algorithm**: Utilizes an algorithm that intelligently selects words for review. It prioritizes words with the lowest scores (indicating greater difficulty) and those with the earliest review dates.
- **Diverse Question Types**: Offers a variety of question types to keep the review process engaging and effective, including multiple choice that asks about the definition, synonym, antonym of a word, and fill-in-the-blank questions that show either the definition or one of the images associated with the word and user has to type in the word.
- **Fully Responsive**: The app is fully responsive and can be used on mobile devices.
### Future Features
- **User Authentication**: Users can create an account and log in to access their data from any device.
- **MongoDB Integration**: Store user data in a database to allow for data persistence across devices.
- **User Profile**: Users can view their profile and see their progress.
- **Performance Tracking**: Users can view their performance and progress over time.
## API
- [WordsAPI](https://www.wordsapi.com/)
- [pexels](https://www.pexels.com/api/)
- Browser Speech Synthesis API
## License
[MIT](https://choosealicense.com/licenses/mit/)
| A Vocabulary Builder app built with React, Tailwind CSS, and HTML. | flashcards,javascript,quiz,react,tailwindcss,vocabulary-builder,vocabulary-learning | 2023-08-03T10:11:40Z | 2023-11-10T00:04:04Z | null | 1 | 1 | 210 | 0 | 1 | 4 | null | null | JavaScript |
thatcodechap/bingo | main | # Welcome to Bingo
## How to play
1. Fill up the tiles in any pattern you like, or use the random fill.
2. Once all the tiles are filled, the first player to join the session will get a prompt to start the game.
3. Players take turns playing. When it's your turn, the background color will turn green.
4. Choose a tile to complete a row, column, or diagonal.
5. The first player to complete 5 rows, columns, or diagonals wins the game! | Bingo is a multiplayer game where players try to strike five rows, columns, or diagonals. Each player starts with a 5x5 grid of tiles, and each tile is numbered from 1 to 25 | bingo,css,game,html,javascript,multiplayer,nodejs | 2023-08-06T18:43:16Z | 2023-08-06T18:41:52Z | null | 1 | 0 | 1 | 1 | 1 | 4 | null | null | JavaScript |
Web3Arabs/DApps-Course | main | # DApps-Course
محتوى الدورة التدريبية **بناء تطبيقات DApps** في **[Web3Arabs](https://www.web3arabs.com)** - الأفضل للمبتدئين للتعرف على اساسيات لغة Solidity ومكتبة React/Nextjs وبناء تطبيقات لامركزية وربطها بالواجهة الامامية
| محتوى الدورة التدريبية بناء تطبيقات DApps في Web3Arabs - الأفضل للمبتدئين للتعرف على اساسيات لغة Solidity ومكتبة React/Nextjs وبناء تطبيقات لامركزية وربطها بالواجهة الامامية | ethersjs,hardhat,javascript,layer2,nextjs,reactjs,smart-contracts,solidity,web3,web3arabs | 2023-08-01T14:13:30Z | 2024-02-21T00:17:52Z | null | 1 | 6 | 13 | 0 | 1 | 4 | null | null | null |
Emin-G/StellarLoom | master | <img src="https://github.com/Emin-G/Img/blob/main/StellarLoom_Pamplet-min.png?raw=true" alt="StellarLoomThumb" width="100%">
# StellarLoom Preview
<p align="center">
<img src="https://github.com/Emin-G/Img/blob/main/StellarLoom_Profile_Round-min.png?raw=true" alt="StellarLoom" width="40%">
</p>
<p align="center">
StellarLoom은 이미 다른 이들에게 스며져 있지만, 여전히 당신의 마음 속에도 깃들 수 있는 안정적이고 효율적인 뮤직봇 입니다.
</p>
<p align="center">
‘Stellar’의 ‘혜성’이라는 의미와, ‘Loom’의 ‘어렴풋이 보이다'라는 뜻이 결합된 StellarLoom은,
기존 Daydream 뮤직봇 프로젝트의 한계를 능가하는 가능성을
어렴풋이 보이는 혜성에 비유해 추상적으로 나타냅니다.
</p>
---
<div align="center">
<img src="https://github.com/Emin-G/Img/blob/main/stellar4.png?raw=true" width="60%">
</div>
<p align="center">
StellarLoom은 심플하고 직관적인 디자인과
</p>
<p align="center">
Daydream 프로젝트에 비해 더욱 안정적이고 많은 수의 스트리밍을 감당할 수 있으며
</p>
<p align="center">
누구나 빠르게 명령어를 사용할 수 있는 간단함을 목표로 개발되고 있습니다.
</p>
- 영상 출처 - 공룡 @rulrudino
- https://youtu.be/Mh02Uv39mQI
- https://youtu.be/42e7hyTiKUE
- **☆☆☆24시간 스트리밍 및 롤모델 삼기 환영 중(아마)☆☆☆**
---
<div align="center">
<a href="https://github.com/Emin-G/Daydream-music-bot">
<img src="https://github.com/Emin-G/Img/blob/main/Daydream_Pamplet.png?raw=true" alt="Daydream" width="45%">
</a>
<a href="https://yupi.arite.studio/">
<img src="https://github.com/Emin-G/Img/blob/main/Yupi_Pamplet.png?raw=true" alt="Yupi" width="45%">
</div>
</a>
<p align="center">
뮤직봇을 처음 다루어 보거나 가볍게 사용려면 Daydream 프로젝트를 참고해주세요.
</p>
<p align="center">
Daydream, StellarLoom 프로젝트를 체험해보고 싶다면 유피를 서버에 초대해보세요!
</p>
---
## 🎉 2.0 업데이트
- 대량 스킵 기능이 추가됬어요. ( /스킵 1 10 -> 1번 ~ 10번 트랙 스킵 )
- 이동 기능이 추가됬어요. ( /이동 1 30 -> 1분 30초 위치로 이동 )
- 스킵 사용 이후 트랙 자동 스킵이 안되던 문제를 해결했어요.
---
## **목차**
### **설치**
- [서버 설정](#서버설정)
- [실행](#실행)
### **기능**
- [재생](#재생)
- [중지](#중지)
- [스킵](#스킵)
- [재생목록](#재생목록)
- [반복](#반복)
- [셔플](#셔플)
- [이동](#이동)
- [* 베이스 (베이스부스트)](#베이스)
- [* 나이트 (나이트코어)](#나이트)
> '*' 는 정식 버전이 아닌 Pre-Release 에 포함된 기능입니다.
# 설치
## 서버설정
**Windows 운영체제를 기준으로 설명합니다.**
.env 파일을 StellarLoom 폴더 내에 생성해주세요.
> BOT_TOKEN=
> CLIENT_ID=
> LAVA_PORT=27017
> LAVA_PASS=stellarloomtemppass
다음 내용을 복사해서 붙여넣어주세요.
**BOT_TOKEN**에 생성한 봇의 토큰을,
**CLIENT_ID**에 봇의 Client ID를 넣어주세요.
봇의 MESSAGE CONTENT INTENT가 켜져있어야 하고 서버 내 메세지 삭제 권한이 필요합니다.
**LAVA_PORT**는 LavaLink 뮤직 서버의 포트를 의미합니다.
**LAVA_PASS**는 LavaLink 뮤직 서버의 비밀번호를 의미합니다.
초기 비밀번호는 **stellarloomtemppass** 으로 되어있습니다.
**LAVA_PORT**와 **LAVA_PASS**는 잘 모르겠다면 건드리지 않는 것이 좋습니다.
많은 사용자를 보유하고 있는 **거대한 봇에 사용**할 경우에는 **LAVA_PASS**를 변경하는 것을 권장합니다.
바꿀때는 .env 파일안의 **LAVA_PASS**와 application.yml 안의 **password**를 동시에 바꿔주어야 정상적으로 작동합니다.
---
위의 사항에서 어려움을 겪었다면 Daydream 프로젝트를 사용하거나, Daydream 프로젝트의 설명을 참고해주세요.
---
StellarLoom은 LavaLink 서버가 구동되고 있어야 정상적으로 작동합니다.
먼저, LavaLink 서버를 구동하기 위해서는 JDK 17 버전의 설치가 필요합니다.
* 이미 JDK 17 버전이 설치되어 있다면 이 단계를 건너 뛰셔도 좋습니다.
https://www.oracle.com/java/technologies/javase/jdk17-archive-downloads.html
위 사이트를 열어주세요.
> <img src="https://github.com/Emin-G/Img/blob/main/stellar6-min.png?raw=true" width="100%">
> 17.x.x 중 가장 최신 버전의 JDK 설치 프로그램을 다운로드 해주세요.
JDK 설치를 완료해주세요.
---
https://github.com/lavalink-devs/Lavalink/releases
위 사이트를 열어주세요.
><img src="https://github.com/Emin-G/Img/blob/main/stellar_fix-min.png?raw=true" width="100%">
>Lavalink.jar를 다운로드 받아주세요. 3.x.x 버전을 권장하고 있습니다.
>3.x.x 중 최대한 최신 버전을 다운로드 받아주세요.
---
><div align="center"><img src="https://github.com/Emin-G/Img/blob/main/stellar2-min.png?raw=true" width="50%"></div>
>Server 폴더를 StellarLoom 폴더 밖으로 꺼내주세요.
---
><div align="center"><img src="https://github.com/Emin-G/Img/blob/main/stellar3-min.png?raw=true" width="30%"></div>
>밖으로 꺼낸 Server 폴더 안에 아까 다운받았던 Lavalink.jar를 넣어주세요.
---
폴더 안의 start.bat을 키면 뮤직 서버가 실행됩니다.
서버가 실행된 후 봇을 키시면 됩니다.
---
# 기능
현재 Daydream 프로젝트에 비해 지원하는 명령어가 적습니다.
점차 추가 해 나갈 예정이니 조큼만 기다려주세요.
## 재생
> /재생 [옵션]
- **옵션**
- 검색어
- 영상 URL
- 재생목록 URL
URL은 **Youtube**, *SoundCloud, BandCamp, Twitch* 를 지원하고 있습니다.
* 볼드체는 정식 지원 나머지는 일단 되긴 한다 입니다.
## 중지
> /중지
## 스킵
> /스킵
> /스킵 [트랙 번호]
> /스킵 [시작 트랙 번호, 끝 트랙 번호]
여러 트랙을 삭제할 수도 있습니다. 1 3은 1 ~ 3번 트랙을 스킵합니다.
- 트랙 번호는 [/재생목록](#재생목록) 을 참조
## 재생목록
> /재생목록
**`트랙 번호`** | 곡 이름
## 반복
> /반복
## 셔플
> /셔플
## 이동
> /이동 [시간]
예를 들어 1 30 은 1분 30초 부터 재생합니다.
## 베이스
> /베이스
베이스부스트(BassBoost) 모드를 키거나 끕니다.
BassBoost 기능과 NightCore 모드는 동시에 사용할 수 없습니다.
## 나이트
> /나이트
나이트코어(NightCore) 모드를 키거나 끕니다.
BassBoost 기능과 NightCore 모드는 동시에 사용할 수 없습니다. | StellarLoom - 거대한 프로젝트를 위한 안정적이고 효율적인 한국어 기반 디스코드 뮤직 봇 (LavaLink, Discord.js v14) | discord,discord-bot,discord-js,discord-js-v14,discord-music,discord-music-bot,discord-voice,discordbot,discordjs,javascript | 2023-07-24T05:13:09Z | 2023-10-14T11:30:12Z | 2023-09-09T14:01:14Z | 1 | 0 | 26 | 0 | 0 | 4 | null | MIT | JavaScript |
anshuman7negi/Kanban_board | development | <a name="readme-top"></a>
<div align="center">
<h3><b>Welcome to our Project</b></h3>
</div>
# 📗 Table of Contents
- [📖 About the Project](#about-project)
- [🛠 Built With](#built-with)
- [Tech Stack](#tech-stack)
- [Key Features](#key-features)
- [💻 Getting Started](#getting-started)
- [Setup](#setup)
- [Prerequisites](#prerequisites)
- [🌍 Online Version](#online-version)
- [👥 Authors](#authors)
- [🔭 Future Features](#future-features)
- [🤝 Contributing](#contributing)
- [⭐️ Show your support](#support)
- [🙏 Acknowledgements](#acknowledgements)
- [📝 License](#license)
# 📖 Flavour Hub <a name="about-project"></a>
**Flavour Hub** is a web application that displays different meals from an API and allows users to like and comment on their favourite meals.
## 🛠 Built With <a name="built-with"></a>
### Tech Stack <a name="tech-stack"></a>
- **[HTML5]**
- **[CSS3]**
- **[Javascript]**
- **[Webpack]**
- **[Jest]**
### Key Features <a name="key-features"></a>
- **[Popup cards]**
- **[Use of MealDB API]**
- **[Use of involvement API]**
<p align="right">(<a href="#readme-top">back to top</a>)</p>
## 💻 Getting Started <a name="getting-started"></a>
To get a local copy up and running, follow these steps.
- **[Clone the repository.]**
- **[Create a directory in your device.]**
### Prerequisites
In order to run this project you need:
- **[A code editor like VS code]**
- **[Internet connection]**
Before running the app, Follow these steps to get the API key(s):
- Go to the website of the API provider(s) and sign up for an account.
- Once you have an account, navigate to the API documentation to find details on how to obtain an API key or credentials.
- Some APIs may require you to create a new project or app to get a unique API key.
- Make sure to review the API provider's terms of service and usage guidelines.
Also:
- npm install
- npm start
### Setup
Clone this repository to your desired folder:
Example commands:
git clone https://github.com/anshuman7negi/Kanban_board.git
cd Kanban_board
<p align="right">(<a href="#readme-top">back to top</a>)</p>
## 🌍 Online Version <a name="online-version"></a>
[Live version](https://anshuman7negi.github.io/Kanban_board/dist/)
## 📹 Video Presentation <a name="Video-Presentation"></a>
[Video Presentation](https://drive.google.com/file/d/1pYBPj9zkxM5IgwO3xaJnGUVq0sK6-s2q/view?usp=sharing)
<p align="right">(<a href="#readme-top">back to top</a>)</p>
## 👥 Authors <a name="authors"></a>
👤 **Bupilipili**
- GitHub: [@bupilipili](https://github.com/bupilipili)
- Twitter: [@ErickBupilipili](https://twitter.com/ErickBupilipili?t=UqGSzTxuad6me1Rf7eplPg&s=08)
- LinkedIn: [ErickBupilipili](https://www.linkedin.com/in/erick-bupilipili-08ba31228)
👤 **Anshuman Singh Negi**
- GitHub: [@githubhandle](https://github.com/anshuman7negi)
- Twitter: [@twitterhandle](https://twitter.com/AnshumanNegi108)
- LinkedIn: [@LinkedIn](https://www.linkedin.com/in/anshuman-singh-negi-33779a224/)
<p align="right">(<a href="#readme-top">back to top</a>)</p>
## 🔭 Future Features <a name="future-features"></a>
- **[Use of frontend frameworks]**
<p align="right">(<a href="#readme-top">back to top</a>)</p>
## 🤝 Contributing <a name="contributing"></a>
Contributions, issues, and feature requests are welcome!
Feel free to check the [isuue](https://github.com/anshuman7negi/Kanban_board/issues).
<p align="right">(<a href="#readme-top">back to top</a>)</p>
## ⭐️ Show your support <a name="support"></a>
If you like this project you can star the repository to make it look better.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
## 🙏 Acknowledgments <a name="acknowledgements"></a>
We would like to thank Microverse for giving us all the necessary knowledge we need to make this project.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
## 📝 License <a name="license"></a>
This project is [MIT](./MIT.md) licensed.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
| A single page website which allows user to give like and comment to there favourite meal. Built with HTML, CSS and Javascript. | javascript,css3,html5,jest,webpack | 2023-07-31T03:29:38Z | 2023-08-04T11:33:04Z | null | 2 | 12 | 120 | 0 | 0 | 4 | null | MIT | JavaScript |
jadaun-sahab/crypto-coin | main | # Getting Started with Create React App
This project was bootstrapped with [Create React App](https://github.com/facebook/create-react-app).
## Available Scripts
In the project directory, you can run:
### `npm start`
Runs the app in the development mode.\
Open [http://localhost:3000](http://localhost:3000) to view it in your browser.
The page will reload when you make changes.\
You may also see any lint errors in the console.
### `npm test`
Launches the test runner in the interactive watch mode.\
See the section about [running tests](https://facebook.github.io/create-react-app/docs/running-tests) for more information.
### `npm run build`
Builds the app for production to the `build` folder.\
It correctly bundles React in production mode and optimizes the build for the best performance.
The build is minified and the filenames include the hashes.\
Your app is ready to be deployed!
See the section about [deployment](https://facebook.github.io/create-react-app/docs/deployment) for more information.
### `npm run eject`
**Note: this is a one-way operation. Once you `eject`, you can't go back!**
If you aren't satisfied with the build tool and configuration choices, you can `eject` at any time. This command will remove the single build dependency from your project.
Instead, it will copy all the configuration files and the transitive dependencies (webpack, Babel, ESLint, etc) right into your project so you have full control over them. All of the commands except `eject` will still work, but they will point to the copied scripts so you can tweak them. At this point you're on your own.
You don't have to ever use `eject`. The curated feature set is suitable for small and middle deployments, and you shouldn't feel obligated to use this feature. However we understand that this tool wouldn't be useful if you couldn't customize it when you are ready for it.
## Learn More
You can learn more in the [Create React App documentation](https://facebook.github.io/create-react-app/docs/getting-started).
To learn React, check out the [React documentation](https://reactjs.org/).
### Code Splitting
This section has moved here: [https://facebook.github.io/create-react-app/docs/code-splitting](https://facebook.github.io/create-react-app/docs/code-splitting)
### Analyzing the Bundle Size
This section has moved here: [https://facebook.github.io/create-react-app/docs/analyzing-the-bundle-size](https://facebook.github.io/create-react-app/docs/analyzing-the-bundle-size)
### Making a Progressive Web App
This section has moved here: [https://facebook.github.io/create-react-app/docs/making-a-progressive-web-app](https://facebook.github.io/create-react-app/docs/making-a-progressive-web-app)
### Advanced Configuration
This section has moved here: [https://facebook.github.io/create-react-app/docs/advanced-configuration](https://facebook.github.io/create-react-app/docs/advanced-configuration)
### Deployment
This section has moved here: [https://facebook.github.io/create-react-app/docs/deployment](https://facebook.github.io/create-react-app/docs/deployment)
### `npm run build` fails to minify
This section has moved here: [https://facebook.github.io/create-react-app/docs/troubleshooting#npm-run-build-fails-to-minify](https://facebook.github.io/create-react-app/docs/troubleshooting#npm-run-build-fails-to-minify)
| TRACK AND TRADE CRYPTO CURRENCIES build by me using reactjs | css,javascript,react,react-native,router-dom | 2023-07-25T14:40:19Z | 2023-08-15T07:33:38Z | null | 1 | 0 | 69 | 0 | 0 | 4 | null | null | JavaScript |
Alok-2002/Starbucks_Landing_Page | main | # Starbucks Landing Page
This repository contains a Starbucks landing page created using HTML, CSS, and JavaScript. The landing page is designed to showcase the Starbucks brand and provide users with an interactive and visually appealing experience.
## Table of Contents
- [Demo](#demo)
- [Features](#features)
- [Technologies](#technologies)
- [Setup](#setup)
- [Usage](#usage)
- [Contributing](#contributing)
- [License](#license)
## Demo
Here's a live demo of the Starbucks landing page: [Starbucks Landing Page Demo](https://starbucks-landing-page-alok-2002.vercel.app)
## Features
- Responsive design: The landing page is optimized to work on various devices and screen sizes.
- Interactive elements: Engaging user interactions with buttons, animations, and more.
- Eye-catching visuals: Attractive layout and images that represent the Starbucks brand.
- Menu display: A section showcasing the Starbucks menu items and options.
- Social media integration: Links to Starbucks' official social media accounts.
## Technologies
The project was built using the following technologies:
- HTML
- CSS
- JavaScript
## Setup
To run this project locally, follow these steps:
1. Clone the repository: `git clone https://github.com/alok-2002/Starbucks_Landing_Page.git`
2. Navigate to the project directory: `cd Starbucks_Landing_Page`
## Usage
After completing the setup, simply open the `index.html` file in your preferred web browser to view the Starbucks landing page.
Feel free to explore the different sections and interact with the various elements on the page.
## Contributing
Contributions to this project are welcome and encouraged! If you find any bugs or have suggestions for improvements, please open an issue or submit a pull request.
1. Fork the repository.
2. Create a new branch: `git checkout -b feature/your-feature-name`
3. Make your changes and commit them: `git commit -m 'Add some feature'`
4. Push the changes to your branch: `git push origin feature/your-feature-name`
5. Submit a pull request.
## License
This project is licensed under the [MIT License](LICENSE). Feel free to use, modify, and distribute the code as per the terms of the license.
---
We hope you enjoy exploring the Starbucks Landing Page! If you have any questions or need further assistance, feel free to contact us.
## Contact:
- **Alok Sharma**
- [sharmaalok02gwl@gmail.com](mailto:sharmaalok02gwl@gmail.com)
- [Website](https://soulfulscribbles.tech/)
| This repository contains a Starbucks landing page created using HTML, CSS, and JavaScript. The landing page is designed to showcase the Starbucks brand and provide users with an interactive and visually appealing experience. | alok-2002,alok-sharma,css,css3,git,github,html,html-css-javascript,javascript,landing-page | 2023-07-21T04:11:15Z | 2023-07-24T15:03:33Z | null | 1 | 0 | 19 | 0 | 0 | 4 | null | MPL-2.0 | CSS |
VarshaRani9/VIDEO-STREAMING-APP | main | # Getting Started with Create React App
This project was bootstrapped with [Create React App](https://github.com/facebook/create-react-app).
## Available Scripts
In the project directory, you can run:
### `npm start`
Runs the app in the development mode.\
Open [http://localhost:3000](http://localhost:3000) to view it in your browser.
The page will reload when you make changes.\
You may also see any lint errors in the console.
### `npm test`
Launches the test runner in the interactive watch mode.\
See the section about [running tests](https://facebook.github.io/create-react-app/docs/running-tests) for more information.
### `npm run build`
Builds the app for production to the `build` folder.\
It correctly bundles React in production mode and optimizes the build for the best performance.
The build is minified and the filenames include the hashes.\
Your app is ready to be deployed!
See the section about [deployment](https://facebook.github.io/create-react-app/docs/deployment) for more information.
### `npm run eject`
**Note: this is a one-way operation. Once you `eject`, you can't go back!**
If you aren't satisfied with the build tool and configuration choices, you can `eject` at any time. This command will remove the single build dependency from your project.
Instead, it will copy all the configuration files and the transitive dependencies (webpack, Babel, ESLint, etc) right into your project so you have full control over them. All of the commands except `eject` will still work, but they will point to the copied scripts so you can tweak them. At this point you're on your own.
You don't have to ever use `eject`. The curated feature set is suitable for small and middle deployments, and you shouldn't feel obligated to use this feature. However we understand that this tool wouldn't be useful if you couldn't customize it when you are ready for it.
## Learn More
You can learn more in the [Create React App documentation](https://facebook.github.io/create-react-app/docs/getting-started).
To learn React, check out the [React documentation](https://reactjs.org/).
### Code Splitting
This section has moved here: [https://facebook.github.io/create-react-app/docs/code-splitting](https://facebook.github.io/create-react-app/docs/code-splitting)
### Analyzing the Bundle Size
This section has moved here: [https://facebook.github.io/create-react-app/docs/analyzing-the-bundle-size](https://facebook.github.io/create-react-app/docs/analyzing-the-bundle-size)
### Making a Progressive Web App
This section has moved here: [https://facebook.github.io/create-react-app/docs/making-a-progressive-web-app](https://facebook.github.io/create-react-app/docs/making-a-progressive-web-app)
### Advanced Configuration
This section has moved here: [https://facebook.github.io/create-react-app/docs/advanced-configuration](https://facebook.github.io/create-react-app/docs/advanced-configuration)
### Deployment
This section has moved here: [https://facebook.github.io/create-react-app/docs/deployment](https://facebook.github.io/create-react-app/docs/deployment)
### `npm run build` fails to minify
This section has moved here: [https://facebook.github.io/create-react-app/docs/troubleshooting#npm-run-build-fails-to-minify](https://facebook.github.io/create-react-app/docs/troubleshooting#npm-run-build-fails-to-minify)
| This is a YouTube clone application crafted using HTML, JavaScript, ReactJs, Redux-toolkit, and enhanced with Tailwind CSS. Featuring search optimization through caching and debouncing techniques, n-level nested comments, and real-time chat streaming. | javascript,reactjs,redux-toolkit,tailwindcss | 2023-07-22T02:52:10Z | 2023-09-02T17:00:14Z | null | 1 | 0 | 5 | 0 | 0 | 4 | null | null | JavaScript |
dmiseev/chatgpt-retrieval-js | main | # chatgpt-retrieval-js
A simple script that enables you to use ChatGPT with your own files for question-answering tasks.
## Installation
```
npm install
```
Modify `.env.dist` to use your own [OpenAI API key](https://platform.openai.com/account/api-keys), and rename it to `.env`.
Place your own files (`.txt`, `.csv`, `.json`, `.md`) in the `data/` folder.
## Example usage
To start the script, run the following command:
```
> npm run start
```
Feel free to customize and enhance the code to suit your specific use-case and data requirements. Happy ChatGPT interaction!
| null | javascript,langchain,openai | 2023-07-26T15:41:40Z | 2023-09-06T14:01:40Z | null | 1 | 0 | 8 | 0 | 2 | 4 | null | MIT | JavaScript |
Ludis-ET/Bilihcare | main |
<a name="readme-top"></a>
[![Contributors][contributors-shield]][contributors-url]
[![Forks][forks-shield]][forks-url]
[![Stargazers][stars-shield]][stars-url]
[![Issues][issues-shield]][issues-url]
[![MIT License][license-shield]][license-url]
[![LinkedIn][linkedin-shield]][linkedin-url]
<!-- PROJECT LOGO -->
<br />
<div align="center">
<a href="https://github.com/Ludis-et/Bilihcare">
<img src="https://github.com/Ludis-ET/Best-README-Template/blob/master/images/logo.png" alt="Logo" width="80" height="80">
</a>
<h3 align="center">Bilihcare</h3>
<p align="center">
For an electronics repairement organization to get orders from customers and manage them efficiently.
<br />
<a href="https://github.com/Ludis-et/Bilihcare"><strong>Explore the docs »</strong></a>
<br />
<br />
<a href="https://bilihcare.vercel.app">View Demo</a>
·
<a href="https://github.com/Ludis-et/Bilihcare/issues">Report Bug</a>
·
<a href="https://github.com/Ludis-et/Bilihcare/issues">Request Feature</a>
</p>
</div>
<!-- TABLE OF CONTENTS -->
<details>
<summary>Table of Contents</summary>
<ol>
<li>
<a href="#about-the-project">About The Project</a>
<ul>
<li><a href="#built-with">Built With</a></li>
</ul>
</li>
<li>
<a href="#getting-started">Getting Started</a>
<ul>
<li><a href="#prerequisites">Prerequisites</a></li>
<li><a href="#installation">Installation</a></li>
</ul>
</li>
<li><a href="#usage">Usage</a></li>
<li><a href="#roadmap">Roadmap</a></li>
<li><a href="#contributing">Contributing</a></li>
<li><a href="#license">License</a></li>
<li><a href="#contact">Contact</a></li>
<li><a href="#acknowledgments">Acknowledgments</a></li>
</ol>
</details>
<!-- ABOUT THE PROJECT -->
[![Product Name Screen Shot][product-screenshot]](static/readme/screencapture-bilihcare-vercel-app-2024-02-15-18_50_59.png)
## About The Project
Welcome to [Your Project Name] - your one-stop solution for electronic repair services. This full-stack web application empowers users to effortlessly order electronic repairs, providing convenience and flexibility in two distinct service models.
### Key Features
- **Order Repair Services:**
- Users can easily place orders for electronic repair services.
- Specify device details, the type of repair needed, and preferred service time.
- **Flexible Service Models:**
- Choose between in-store repair or on-site service at your doorstep.
- Enjoy the convenience of having technicians come to your home for repairs.
- **Interactive Blog Section:**
- Stay informed and entertained with our blog section.
- Discover new articles, tips, and insights related to electronic devices and repairs.
### How It Works
1. **Order Placement:**
- Navigate to the [Order Page] to initiate the repair process.
- Provide necessary details about your device and the issue.
2. **Service Selection:**
- Choose between in-store repair or on-site service.
- Pick a convenient time for the repair to take place.
3. **Blog Exploration:**
- Visit our [Blog Section] to stay updated on the latest trends, tips, and news.
- Engage with our community through comments and discussions.
### Built With
* [](https://www.djangoproject.com/)
* [](https://developer.mozilla.org/en-US/docs/Web/HTML)
* [](https://getbootstrap.com/)
* [](https://www.w3.org/Style/CSS/Overview.en.html)
* [](https://developer.mozilla.org/en-US/docs/Web/JavaScript)
* [](https://www.python.org/)
* [](https://jquery.com/)
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- GETTING STARTED -->
## Getting Started
This is an example of how you may give instructions on setting up your Django project locally. To get a local copy up and running, follow these simple example steps.
### Prerequisites
This is an example of how to list things you need to use the software and how to install them.
* Python
```sh
# Install Python via your preferred method, e.g., using pyenv
pyenv install 3.9.18
```
### Installation
_Below is an example of how you can instruct your audience on installing and setting up this project into your local machine and run_
1. **Clone the repo**
```sh
git clone https://github.com/Ludis-ET/Bilihcare.git
```
2. **Navigate to the project directory**
```sh
cd Bilihcare
```
3. **Create a virtual environment**
```sh
python -m venv venv
```
4. **Activate the virtual environment**
- On Windows:
```sh
.\venv\Scripts\activate
```
- On Unix or MacOS:
```sh
source venv/bin/activate
```
5. **Install required packages**
```sh
pip install -r requirements.txt
```
6. **Apply migrations**
```sh
python manage.py migrate
```
7. **Run the development server**
```sh
python manage.py runserver
```
<p align="right">(<a href="#readme-top">back to top</a>)</p>
[![Product Name Screen Shot][product-screenshott]](static/readme/screencapture-localhost-8000-admin-page-2024-02-15-19_46_08.png)
<!-- USAGE EXAMPLES -->
## Usage
Remember to replace `3.9.18` with your preferred Python version if it's different. If you have any specific API keys or configuration steps related to your Django app, you can include them in the relevant sections of this guide.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- ROADMAP
## Roadmap
- [x] Add Changelog
- [x] Add back to top links
- [ ] Add Additional Templates w/ Examples
- [ ] Add "components" document to easily copy & paste sections of the readme
- [ ] Multi-language Support
- [ ] Chinese
- [ ] Spanish -->
See the [open issues](https://github.com/Ludis-et/Bilihcare/issues) for a full list of proposed features (and known issues).
<!-- <p align="right">(<a href="#readme-top">back to top</a>)</p> -->
<!-- CONTRIBUTING -->
## Contributing
Contributions are what make the open source community such an amazing place to learn, inspire, and create. Any contributions you make are **greatly appreciated**.
If you have a suggestion that would make this better, please fork the repo and create a pull request. You can also simply open an issue with the tag "enhancement".
Don't forget to give the project a star! Thanks again!
1. Fork the Project
2. Create your Feature Branch (`git checkout -b feature/AmazingFeature`)
3. Commit your Changes (`git commit -m 'Add some AmazingFeature'`)
4. Push to the Branch (`git push origin feature/AmazingFeature`)
5. Open a Pull Request
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- LICENSE -->
## License
Distributed under the MIT License. See `LICENSE.txt` for more information.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- CONTACT -->
## Contact
Your Name - [instagram](https://instagram.com/lulsgd) - leulsegedmelaku1020@gmail.com
Project Link: [https://github.com/ludis-et/bilihcare](https://github.com/ludis-et/bilihcare)
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!--
## Acknowledgments
Use this space to list resources you find helpful and would like to give credit to. I've included a few of my favorites to kick things off!
* [Choose an Open Source License](https://choosealicense.com)
* [GitHub Emoji Cheat Sheet](https://www.webpagefx.com/tools/emoji-cheat-sheet)
* [Malven's Flexbox Cheatsheet](https://flexbox.malven.co/)
* [Malven's Grid Cheatsheet](https://grid.malven.co/)
* [Img Shields](https://shields.io)
* [GitHub Pages](https://pages.github.com)
* [Font Awesome](https://fontawesome.com)
* [React Icons](https://react-icons.github.io/react-icons/search)
<p align="right">(<a href="#readme-top">back to top</a>)</p> -->
<!-- MARKDOWN LINKS & IMAGES -->
<!-- https://www.markdownguide.org/basic-syntax/#reference-style-links -->
[contributors-shield]: https://img.shields.io/github/contributors/Ludis-et/Bilihcare.svg?style=for-the-badge
[contributors-url]: https://github.com/Ludis-et/Bilihcare/graphs/contributors
[forks-shield]: https://img.shields.io/github/forks/Ludis-et/Bilihcare.svg?style=for-the-badge
[forks-url]: https://github.com/Ludis-et/Bilihcare/network/members
[stars-shield]: https://img.shields.io/github/stars/Ludis-et/Bilihcare.svg?style=for-the-badge
[stars-url]: https://github.com/Ludis-et/Bilihcare/stargazers
[issues-shield]: https://img.shields.io/github/issues/Ludis-et/Bilihcare.svg?style=for-the-badge
[issues-url]: https://github.com/Ludis-et/Bilihcare/issues
[license-shield]: https://img.shields.io/github/license/Ludis-et/Bilihcare.svg?style=for-the-badge
[license-url]: https://github.com/Ludis-et/Bilihcare/blob/master/LICENSE.txt
[linkedin-shield]: https://img.shields.io/badge/-LinkedIn-black.svg?style=for-the-badge&logo=linkedin&colorB=555
[linkedin-url]: https://linkedin.com/in/othneildrew
[product-screenshot]: static/readme/screencapture-bilihcare-vercel-app-2024-02-15-18_50_59.png
[product-screenshott]: static/readme/screencapture-localhost-8000-admin-page-2024-02-15-19_46_08.png
[Next.js]: https://img.shields.io/badge/Django?style=for-the-badge&logo=django
[Next-url]: https://www.djangoproject.com/
[React.js]: https://img.shields.io/badge/React-20232A?style=for-the-badge&logo=react&logoColor=61DAFB
[React-url]: https://reactjs.org/
[Vue.js]: https://img.shields.io/badge/Vue.js-35495E?style=for-the-badge&logo=vuedotjs&logoColor=4FC08D
[Vue-url]: https://vuejs.org/
[Angular.io]: https://img.shields.io/badge/Angular-DD0031?style=for-the-badge&logo=angular&logoColor=white
[Angular-url]: https://angular.io/
[Svelte.dev]: https://img.shields.io/badge/Svelte-4A4A55?style=for-the-badge&logo=svelte&logoColor=FF3E00
[Svelte-url]: https://svelte.dev/
[Laravel.com]: https://img.shields.io/badge/Laravel-FF2D20?style=for-the-badge&logo=laravel&logoColor=white
[Laravel-url]: https://laravel.com
[Bootstrap.com]: https://img.shields.io/badge/Bootstrap-563D7C?style=for-the-badge&logo=bootstrap&logoColor=white
[Bootstrap-url]: https://getbootstrap.com
[JQuery.com]: https://img.shields.io/badge/jQuery-0769AD?style=for-the-badge&logo=jquery&logoColor=white
[JQuery-url]: https://jquery.com
| 🔧 This project is an Electronics Repair Hub, offering a dynamic full-stack experience for expert repair services across a variety of devices. With streamlined online bookings and a network of skilled technicians, this platform ensures efficient and reliable electronics repair. Join us in the mission of bringing devices back to life! 💻 | bootstrap,css,django,html,javascript,jquery,repair | 2023-07-30T13:37:20Z | 2024-04-22T19:06:56Z | null | 1 | 0 | 74 | 0 | 0 | 4 | null | Apache-2.0 | CSS |
JimHans/OPTMapGenerator | main | <p align="center">
<img src="./assets/app.png" width="128" height="128"></p>
<h1 align="center"> OPT Map Generator </h1>
<h3 align="center"> 11th OPT Competition Map Generator based on Electron.</h3>
<br/>
<p align="center">
<img src="https://img.shields.io/badge/build-passing-green.svg?style=flat-square">
<img src="https://img.shields.io/github/package-json/v/JimHans/OPTMapGenerator?color=pink&style=flat-square">
<img src="https://img.shields.io/github/downloads/JimHans/OPTMapGenerator/total?color=orange&style=flat-square">
<img src="https://img.shields.io/badge/Electron-25.3.1-blue.svg?style=flat-square">
<img src="https://img.shields.io/badge/License-GPL v3.0-purple.svg?style=flat-square">
</p>
---
### 基于`Electron`框架的第十一届全国大学生光电设计竞赛小车迷宫生成客户端
### 本程序生成引擎基于全国大学生光电设计竞赛当前地图生成规则设计
## 🎰 支持功能：
- [x] 根据比赛规则自动生成场地摆放参考图与藏宝图
- [x] 一键打印藏宝图为PDF或通过打印机打印藏宝图
- [x] 一键保存参考图与藏宝图文件至本地
- [ ] 一键批量生成藏宝图
## 📥下载：
本项目提供Windows x64 可执行安装程序，并为不方便安装的用户提供免安装版本，免安装版本为压缩包，解压后即可使用。
稳定版：[Release Download](https://github.com/JimHans/OPTMapGenerator/releases/latest)
## 💻软件截图：
<p align="center"><img src="./assets/screenshot.png" width=100% style='aspect-ratio:1/0.85'></p>
## 🧡感谢：
本项目由UESTC × AEA 联合开发
This Program is open sourced under the GPL v3.0 license.
本程序基于 GPL v3.0 License 开源，不得用于商业用途 | 第十一届光电设计竞赛小车迷宫地图生成器 | 11th OPT Match Labyrinth Map Generator | electron,javascript,winui3 | 2023-08-02T11:53:49Z | 2023-08-23T02:53:21Z | 2023-08-20T17:25:25Z | 1 | 0 | 11 | 0 | 0 | 4 | null | GPL-3.0 | JavaScript |
shyamtawli/sheetcoder | master | null | A Leetcode clone using MERN Stack. | express,javascript,mern,mern-stack,mern-stack-development,mongodb,react | 2023-07-22T14:13:45Z | 2023-08-29T14:15:52Z | null | 1 | 0 | 39 | 1 | 0 | 4 | null | null | JavaScript |
Ludis-ET/Ha-Belu | main |
<a name="readme-top"></a>
[![Contributors][contributors-shield]][contributors-url]
[![Forks][forks-shield]][forks-url]
[![Stargazers][stars-shield]][stars-url]
[![Issues][issues-shield]][issues-url]
[![MIT License][license-shield]][license-url]
[![LinkedIn][linkedin-shield]][linkedin-url]
<!-- PROJECT LOGO -->
<br />
<div align="center">
<a href="https://github.com/Ludis-et/ha-belu">
<img src="https://github.com/Ludis-ET/Best-README-Template/blob/master/images/logo.png" alt="Logo" width="80" height="80">
</a>
<h3 align="center">Ha Belu School Management System</h3>
<p align="center">
A comprehensive educational platform that empowers students to check results, chat, and access courses, while providing teachers, managers, and staff with tools to manage content, results, and overall website settings.
<br />
<a href="https://github.com/Ludis-et/ha-belu"><strong>Explore the docs »</strong></a>
<br />
<br />
<a href="https://ha-belu.vercel.app">View Demo</a>
·
<a href="https://github.com/Ludis-et/ha-belu/issues">Report Bug</a>
·
<a href="https://github.com/Ludis-et/ha-belu/issues">Request Feature</a>
</p>
</div>
<!-- TABLE OF CONTENTS -->
<details>
<summary>Table of Contents</summary>
<ol>
<li>
<a href="#about-the-project">About The Project</a>
<ul>
<li><a href="#built-with">Built With</a></li>
</ul>
</li>
<li>
<a href="#getting-started">Getting Started</a>
<ul>
<li><a href="#prerequisites">Prerequisites</a></li>
<li><a href="#installation">Installation</a></li>
</ul>
</li>
<li><a href="#usage">Usage</a></li>
<li><a href="#roadmap">Roadmap</a></li>
<li><a href="#contributing">Contributing</a></li>
<li><a href="#license">License</a></li>
<li><a href="#contact">Contact</a></li>
<li><a href="#acknowledgments">Acknowledgments</a></li>
</ol>
</details>
<!-- ABOUT THE PROJECT -->
[product-screenshot]: media/readme/home-page.png
[![Product Name Screen Shot][product-screenshot]](media/readme/home-page.png)
## About The Project
For visitors who haven't logged in yet, our website offers a welcoming environment filled with valuable content. They have unrestricted access to browse through a variety of informative blog posts, gaining insights into educational topics and the latest updates. Additionally, unregistered users can directly communicate with the manager, providing a channel for inquiries, feedback, or any assistance they may require. Creating an account is a seamless process, allowing individuals to become part of our educational community, unlocking personalized features and accessing a plethora of resources. Should they ever encounter difficulties with account access, our user-friendly system facilitates a straightforward account recovery process, ensuring a hassle-free experience for every user interacting with our platform.
[product-screenshott]: media/readme/student-dashboard.png
[![Product Name Screen Shot][product-screenshott]](media/readme/student-dashboard.png)
## Student User Type
Students on our platform enjoy a rich learning experience with a variety of features tailored to their academic journey. They have the privilege to explore and enroll in courses relevant to their interests, interact with peers through course comments, and stay updated by subscribing to their preferred subjects. Our extensive digital library provides students with convenient access to a plethora of softcopy books, fostering a culture of continuous learning. This holistic approach aims to empower students, not just academically but also by nurturing a sense of community and intellectual curiosity within our educational ecosystem.
In addition to the academic offerings, students can delve into a vibrant community where they can engage in discussions, share insights, and foster collaborative learning. The platform's interactive features enable students to comment on course materials, creating a dynamic environment for knowledge exchange. The subscription feature ensures that students stay informed about updates, announcements, and new course offerings, enhancing their educational experience. With a user-friendly interface and diverse resources, our platform strives to make the learning journey seamless, enjoyable, and intellectually rewarding for every student.
[product-screenshottt]: media/readme/teacher-dashboard.png
[![Product Name Screen Shot][product-screenshottt]](media/readme/teacher-dashboard.png)
## Teacher User Type
Teachers play a pivotal role in shaping the educational landscape on our platform. Empowered with dedicated rooms, they can seamlessly manage and enrich the learning experience for their students. Teachers have the capability to create and share insightful blog posts, contribute to a repository of educational resources, and effortlessly input and access student results. The platform provides a collaborative space where teachers can foster meaningful interactions, ensuring effective communication and support within the academic community. With tools designed for streamlined content creation and result management, our platform empowers teachers to inspire and guide their students toward academic excellence.
Additionally, teachers have the privilege of offering a diverse range of courses, catering to the unique needs and interests of their students. These courses serve as a gateway to comprehensive and engaging learning experiences, allowing teachers to impart knowledge and skills in an interactive manner. The platform's library feature further augments the teaching process, providing teachers with the ability to curate a digital collection of resources, including softcopy books, enhancing the richness of educational content available to students. This comprehensive approach ensures that teachers have the tools and resources necessary to create a dynamic and supportive learning environment that goes beyond traditional boundaries.
[product-screenshotttt]: media/readme/manager-dashboard.png
[![Product Name Screen Shot][product-screenshotttt]](media/readme/manager-dashboard.png)
## Manager and Staff User Types
Managers play a pivotal role in overseeing the seamless functioning of the entire educational platform. They wield administrative powers to manage users, control website settings, and ensure the efficient operation of various functionalities. From user management to overseeing reports and statistics, managers contribute to the strategic direction of the platform, making data-driven decisions to enhance overall performance.
Staff members, on the other hand, hold key responsibilities in generating report cards, adding and managing academic results, and performing essential administrative tasks. Their role extends to maintaining student records, facilitating smooth communication among users, and handling day-to-day operations that contribute to the overall efficiency of the educational ecosystem. Together, managers and staff form an integral part of the platform's backbone, ensuring that all aspects run smoothly for the benefit of students, teachers, and the entire learning community.
## Key Features
### 🌐 User-Centric Roles
- **Students:** Explore courses, view academic results, and engage with peers through chat. Access a digital library for softcopy books.
- **Teachers:** Manage blogs, courses, and student results in dedicated rooms, fostering an interactive learning environment.
- **Managers:** Oversee the entire website, manage user settings, and ensure optimal functionality.
- **Staff:** Generate report cards, manage academic results, and contribute to day-to-day operations.
### 🔓 Open Access
- **Non-logged-in Users:** Access blog posts, send messages to the manager, create accounts, and recover forgotten accounts without logging in.
### 🚀 Interactive Learning Environment
- **Collaborative Features:** Students can comment on courses, subscribe to updates, and engage in discussions for an enhanced learning experience.
### 📚 Digital Library
- **Extensive Resources:** Comprehensive library offering a variety of softcopy books for further learning.
### ⚙️ Efficient Administration
- **Managerial Control:** Managers have administrative powers to manage users, control settings, and make data-driven decisions.
- **Staff Operations:** Critical tasks such as generating report cards and managing academic results are handled by staff.
### 🎨 User-Friendly Interface
- **Intuitive Design:** User-friendly interface for easy navigation and a seamless user experience.
### 📧 Communication Channels
- **Seamless Messaging:** Effective communication through built-in messaging features, fostering a connected learning community.
### 🔐 Secure and Accessible
- **User Authentication:** Secure login system for data protection, along with a hassle-free account recovery process.
### 🛠️ Technologies Used
* [](https://www.djangoproject.com/)
* [](https://developer.mozilla.org/en-US/docs/Web/HTML)
* [](https://getbootstrap.com/)
* [](https://www.w3.org/Style/CSS/Overview.en.html)
* [](https://developer.mozilla.org/en-US/docs/Web/JavaScript)
* [](https://www.python.org/)
* [](https://jquery.com/)
* [](https://developer.mozilla.org/en-US/docs/Web/Guide/AJAX)
* [](https://mail.google.com/)
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- GETTING STARTED -->
## Getting Started
This is an example of how you may give instructions on setting up your Django project locally. To get a local copy up and running, follow these simple example steps.
### Prerequisites
This is an example of how to list things you need to use the software and how to install them.
* Python
```sh
# Install Python via your preferred method, e.g., using pyenv
pyenv install 3.9.18
```
### Installation
_Below is an example of how you can instruct your audience on installing and setting up this project into your local machine and run_
1. **Clone the repo**
```sh
git clone https://github.com/Ludis-ET/ha-belu.git
```
2. **Navigate to the project directory**
```sh
cd ha-belu
```
3. **Create a virtual environment**
```sh
python -m venv venv
```
4. **Activate the virtual environment**
- On Windows:
```sh
.\venv\Scripts\activate
```
- On Unix or MacOS:
```sh
source venv/bin/activate
```
5. **Install required packages**
```sh
pip install -r requirements.txt
```
6. **Apply migrations**
```sh
python manage.py migrate
```
7. **Run the development server**
```sh
python manage.py runserver
```
[product-screenshottttt]: media/readme/blog-post.png
[![Product Name Screen Shot][product-screenshottttt]](media/readme/blog-post.png)
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- USAGE EXAMPLES -->
## Usage
Remember to replace `3.9.18` with your preferred Python version if it's different. If you have any specific API keys or configuration steps related to your Django app, you can include them in the relevant sections of this guide.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- ROADMAP
## Roadmap
- [x] Add Changelog
- [x] Add back to top links
- [ ] Add Additional Templates w/ Examples
- [ ] Add "components" document to easily copy & paste sections of the readme
- [ ] Multi-language Support
- [ ] Chinese
- [ ] Spanish -->
See the [open issues](https://github.com/Ludis-et/ha-belu/issues) for a full list of proposed features (and known issues).
<!-- <p align="right">(<a href="#readme-top">back to top</a>)</p> -->
<!-- CONTRIBUTING -->
## Contributing
Contributions are what make the open source community such an amazing place to learn, inspire, and create. Any contributions you make are **greatly appreciated**.
If you have a suggestion that would make this better, please fork the repo and create a pull request. You can also simply open an issue with the tag "enhancement".
Don't forget to give the project a star! Thanks again!
1. Fork the Project
2. Create your Feature Branch (`git checkout -b feature/AmazingFeature`)
3. Commit your Changes (`git commit -m 'Add some AmazingFeature'`)
4. Push to the Branch (`git push origin feature/AmazingFeature`)
5. Open a Pull Request
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- LICENSE -->
## License
Distributed under the MIT License. See `LICENSE.txt` for more information.
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!-- CONTACT -->
## Contact
Ludis - [instagram](https://instagram.com/lulsgd) - leulsegedmelaku1020@gmail.com
Project Link: [https://github.com/ludis-et/ha-belu](https://github.com/ludis-et/ha-belu)
<p align="right">(<a href="#readme-top">back to top</a>)</p>
<!--
## Acknowledgments
Use this space to list resources you find helpful and would like to give credit to. I've included a few of my favorites to kick things off!
* [Choose an Open Source License](https://choosealicense.com)
* [GitHub Emoji Cheat Sheet](https://www.webpagefx.com/tools/emoji-cheat-sheet)
* [Malven's Flexbox Cheatsheet](https://flexbox.malven.co/)
* [Malven's Grid Cheatsheet](https://grid.malven.co/)
* [Img Shields](https://shields.io)
* [GitHub Pages](https://pages.github.com)
* [Font Awesome](https://fontawesome.com)
* [React Icons](https://react-icons.github.io/react-icons/search)
<p align="right">(<a href="#readme-top">back to top</a>)</p> -->
<!-- MARKDOWN LINKS & IMAGES -->
<!-- https://www.markdownguide.org/basic-syntax/#reference-style-links -->
[contributors-shield]: https://img.shields.io/github/contributors/Ludis-et/ha-belu.svg?style=for-the-badge
[contributors-url]: https://github.com/Ludis-et/ha-belu/graphs/contributors
[forks-shield]: https://img.shields.io/github/forks/Ludis-et/ha-belu.svg?style=for-the-badge
[forks-url]: https://github.com/Ludis-et/ha-belu/network/members
[stars-shield]: https://img.shields.io/github/stars/Ludis-et/ha-belu.svg?style=for-the-badge
[stars-url]: https://github.com/Ludis-et/ha-belu/stargazers
[issues-shield]: https://img.shields.io/github/issues/Ludis-et/ha-belu.svg?style=for-the-badge
[issues-url]: https://github.com/Ludis-et/ha-belu/issues
[license-shield]: https://img.shields.io/github/license/Ludis-et/ha-belu.svg?style=for-the-badge
[license-url]: https://github.com/Ludis-et/ha-belu/blob/master/LICENSE.txt
[linkedin-shield]: https://img.shields.io/badge/-LinkedIn-black.svg?style=for-the-badge&logo=linkedin&colorB=555
[linkedin-url]: https://linkedin.com/in/othneildrew
[product-screenshot]: static/readme/screencapture-ha-belu-vercel-app-2024-02-15-18_50_59.png
[product-screenshott]: static/readme/screencapture-localhost-8000-admin-page-2024-02-15-19_46_08.png
[Next.js]: https://img.shields.io/badge/Django?style=for-the-badge&logo=django
[Next-url]: https://www.djangoproject.com/
[React.js]: https://img.shields.io/badge/React-20232A?style=for-the-badge&logo=react&logoColor=61DAFB
[React-url]: https://reactjs.org/
[Vue.js]: https://img.shields.io/badge/Vue.js-35495E?style=for-the-badge&logo=vuedotjs&logoColor=4FC08D
[Vue-url]: https://vuejs.org/
[Angular.io]: https://img.shields.io/badge/Angular-DD0031?style=for-the-badge&logo=angular&logoColor=white
[Angular-url]: https://angular.io/
[Svelte.dev]: https://img.shields.io/badge/Svelte-4A4A55?style=for-the-badge&logo=svelte&logoColor=FF3E00
[Svelte-url]: https://svelte.dev/
[Laravel.com]: https://img.shields.io/badge/Laravel-FF2D20?style=for-the-badge&logo=laravel&logoColor=white
[Laravel-url]: https://laravel.com
[Bootstrap.com]: https://img.shields.io/badge/Bootstrap-563D7C?style=for-the-badge&logo=bootstrap&logoColor=white
[Bootstrap-url]: https://getbootstrap.com
[JQuery.com]: https://img.shields.io/badge/jQuery-0769AD?style=for-the-badge&logo=jquery&logoColor=white
[JQuery-url]: https://jquery.com
| "🚀 Explore the Ha Belu School Management System on GitHub—an open-source project transforming education admin! 📚 Join our cool community to shape the future of education management with this scalable, efficient platform. Let's make school management fun and innovative together! 🎉" | ajax,bootstrap,css,django,django-application,django-framework,django-project,html,html-css-javascript,html5 | 2023-07-30T13:46:42Z | 2024-04-19T07:49:26Z | null | 1 | 0 | 42 | 0 | 0 | 4 | null | null | CSS |
Accountable-SA/accountable-jsvat | main | <h1><p align="center">@accountable/jsvat</p></h1>
<p align="center">Check the validity of the format of a VAT number. No dependencies</p>
<p align="center">
<a href="https://www.npmjs.com/package/@accountable/jsvat">
<img src="https://img.shields.io/npm/v/@accountable/jsvat.svg?style=flat-square&logo=npm" alt="npm">
</a>
<a href="http://makeapullrequest.com">
<img src="https://img.shields.io/badge/PRs-welcome-brightgreen.svg?style=flat-square" alt="PRs Welcome">
</a>
<a href="https://github.com/@accountable/jsvat/blob/master/LICENSE">
<img src="https://img.shields.io/badge/license-MIT-blue.svg?style=flat-square" alt="GitHub license">
</a>
</p>
## Disclaimer
This library is a fork of [jsvat](https://github.com/se-panfilov/jsvat) which in no longer maintained and all new pull requests to it are ignored for long time.
So in [Accountable](https://www.accountable.eu/), we thought it would be great to add support for the new VAT number format and keep the library up to date and easily maintained as it is part of our day to day work.
## What is it?
Small library to check validity VAT numbers (European + some others counties). ([learn more][1] about VAT)
- Rewritten into Typescript :new:
- No dependencies
- No http calls
- 2-step checks: math + regexp
- Tree-shakeable
- Extendable
- Separate checks for valid VAT and valid VAT format
- Dynamically add/remove countries with which you want to check the VAT
- Detecting possible country before you finish
- Typescript
## Installation
via **npm**:
```bash
npm i @accountable/jsvat
```
via **yarn**:
```bash
yarn add @accountable/jsvat
```
## Getting Started
- check against specific countries
```javascript
import { checkVAT, belgium, austria } from '@accountable/jsvat';
checkVAT('BE0411905847', [belgium]); // true: accept only Belgium VATs
checkVAT('BE0411905847', [belgium, austria]); // true: accept only Belgium or Austria VATs
checkVAT('BE0411905847', [austria]); // false: accept only Austria VATs
```
- check against all supported countries
```javascript
import { checkVAT } from '@accountable/jsvat';
checkVAT('BE0411905847'); // no need to pass countries as all supported countries will be used as default behavior
```
- check against all supported countries except specific ones
```javascript
import { checkVAT, countriesMap } from '@accountable/jsvat';
const { france, germany, ...countriesToValidate } = countriesMap;
checkVAT('BE0411905847', countriesToValidate);
```
## Return value
`checkVAT()` returns `VatCheckResult` object:
```typescript
export interface VatCheckResult {
value?: string; // 'BE0411905847': your VAT without extra characters (like '-', spaces, etc)
isValid: boolean; // The main result. Indicates if VAT is correct against provided countries or not
isValidFormat: boolean; // Indicates the validation of the format of VAT only. E.g. "BE0411905847" is a valid VAT, and "BE0897221791" is not. But they both has valid format, so "isValidFormat" will return "true"
isSupportedCountry: boolean; // Indicates if "jsvat" could recognize the VAT. Sometimes you want to understand - if it's an invalid VAT from supported country or from an unknown one
country?: {
// VAT's country (null if not found). By "supported" I mean imported.
name: string; // ISO country name of VAT
isoCode: {
// Country ISO codes
short: string;
long: string;
numeric: string;
};
};
}
```
## List of supported Countries:
- 🇦🇩 Andorra
- 🇦🇹 Austria
- 🇧🇪 Belgium
- 🇧🇷 Brazil
- 🇧🇬 Bulgaria
- 🇭🇷 Croatia
- 🇨🇾 Cyprus
- 🇨🇿 Czech republic
- 🇩🇰 Denmark
- 🇪🇪 Estonia
- 🇪🇺 Europe
- 🇫🇮 Finland
- 🇫🇷 France
- 🇩🇪 Germany
- 🇬🇷 Greece
- 🇭🇺 Hungary
- 🇮🇪 Ireland
- 🇮🇹 Italy
- 🇱🇻 Latvia
- 🇱🇹 Lithuania
- 🇱🇺 Luxembourg
- 🇲🇹 Malta
- 🇳🇱 Netherlands
- 🇳🇴 Norway
- 🇵🇱 Poland
- 🇵🇹 Portugal
- 🇷🇴 Romania
- 🇷🇺 Russia
- 🇷🇸 Serbia
- 🇸🇰 Slovakia Republic
- 🇸🇮 Slovenia
- 🇪🇸 Spain
- 🇸🇪 Sweden
- 🇬🇧 United Kingdom
- 🇨🇭 Switzerland
## Extend countries list - add your own country
You can add your own country.
In general `Country` should implement following structure:
```typescript
interface Country {
name: string;
codes: ReadonlyArray<string>;
rules: {
multipliers: {}; // you can leave it empty
regex: ReadonlyArray<RegExp>;
};
} & ({
calcFn: (vat: string, options?: object) => boolean; // use this if you want to check only format of VAT
} | {
calcWithFormatFn: (vat: string, options?: object) => {isValid: boolean, vat: string}; // use this if you want to check format of VAT and re-format it
})
```
Example:
```javascript
import { checkVAT } from '@accountable/jsvat';
export const wonderland = {
name: 'Wonderland',
codes: ['WD', 'WDR', '999'], // This codes should follow ISO standards (short, long and numeric), but it's your own business
calcFn: (vat) => {
return vat.length === 10;
},
rules: {
regex: [/^(WD)(\d{8})$/],
},
};
checkVAT('WD12345678', [wonderland]); // true
```
## About modules... ES6 / CommonJS
jsvat build includes `es6`, `commonjs`, `amd`, `umd` and `system` builds at the same time.
By default you will stick to `es6` version for browsers and build tools (webpack, etc):
which expects you to import it as
```javascript
import { checkVAT, belgium, austria } from '@accountable/jsvat';
```
Node.js automatically will pick up `CommonJS` version by default.
Means you could import it like:
```jsx harmony
// Modern Frontend and Node
const { checkVAT, belgium, austria } = require('@accountable/jsvat');
// Node.js
const { checkVAT, belgium, austria } = require('@accountable/jsvat');
// Legacy Frontend
<script src='whatever/jsvat/lib/umd/index.js'></script>;
```
Alternatively you can specify which module system you do want, e.g.:
```jsx harmony
// CommonJS (i.g nodejs)
const { checkVAT, belgium, austria } = require('jsvat/lib/commonjs');
// ES6
import { checkVAT, belgium, austria } from 'jsvat/lib/es6';
```
## How `@accountable/jsvat` checks validity?
There is 2-step check:
1. Compare with list of Regexps;
For example regexp for austria is `/^(AT)U(\d{8})$/`.
Looks like `ATU99999999` is valid (it's satisfy the regexp), but actually it's should be invalid.
2. Some magic mathematical counting;
Here we make some mathematical calculation (different for each country).
After that we may be sure that `ATU99999999`and for example `ATV66889218` isn't valid, but `ATU12011204` is valid.
**Note:** VAT numbers of some countries should ends up with special characters. Like '01' for Sweden or "L" for Cyprus. If 100% real VAT doesn't fit, try to add proper appendix.
[1]: https://en.wikipedia.org/wiki/VAT_identification_number
| Check the validity of the format of a VAT number | eu-vat-number,javascript,typescript,vat,vat-number,vat-number-format-validator,vat-number-validation,vat-validator | 2023-08-02T07:48:39Z | 2024-05-02T14:31:53Z | null | 3 | 12 | 21 | 0 | 0 | 4 | null | MIT | TypeScript |
shubhamashish33/quick-note | main |
# Quick Note Chrome Extension
The Quick Notes Chrome Extension allows you to add and remove quick notes right from your Chrome browser. You can use this extension to jot down short pieces of information, reminders, or anything else you want to keep handy.
## Installation
Follow these steps to install the Quick Notes Chrome Extension:
1. **Clone or download the repository:**
Clone this repository to your local machine using the following command:
``` bash
git clone https://github.com/shubhamashish33/quick-note.git
```
Alternatively, you can download the ZIP file and extract it to a local folder.
2. **Open Chrome Extensions page:**
- Open Google Chrome and type `chrome://extensions/` in the address bar.
- Alternatively, you can access the Extensions page by clicking the three-dot menu (top right corner) -> More tools -> Extensions.
3. **Enable Developer mode:**
In the top-right corner of the Extensions page, enable "Developer mode" by toggling the switch.
4. **Load the extension:**
- Click on the "Load unpacked" button that appears after enabling Developer mode.
- Select the folder where you cloned or extracted the extension files (the folder containing the `manifest.json` file).
5. **Extension Added:**
You should see the "Quick Notes" extension icon added to your Chrome toolbar.
6. **Pin in to Toolbar**
Just pin in to your toolbar by going into chrome extension settings
## How to Use
1. **Open the extension:**
- Click on the "Quick Notes" extension icon in the Chrome toolbar. This will open the Quick Notes popup.
2. **Add a new note:**
- Type your note in the input field provided.
- Click the "Add to Note" button to add the note.
3. **Remove a note:**
- Each note in the list has a red cross (✕) icon next to it.
- Click on the cross icon to remove the respective note.
4. **View saved notes:**
- All your saved notes will be displayed below the input field.
- Scroll through the list to view all notes.
## Uninstalling the Extension
To uninstall the Quick Notes Chrome Extension, follow these steps:
1. Click the three-dot menu in the top-right corner of Google Chrome.
2. Go to More tools -> Extensions.
3. Find the "Quick Notes" extension in the list.
4. Click the "Remove" button next to the extension.
5. Confirm the removal when prompted.
## Support and Feedback
If you encounter any issues or have suggestions for improvement, please feel free to [open an issue](https://github.com/shubhamashish33/quick-note/issues). We appreciate your feedback and are here to help!
## License
This extension is open-source and licensed under the [MIT License](LICENSE).
---
We hope you find this Quick Notes Chrome Extension useful for keeping track of your quick thoughts and reminders. If you have any questions or need further assistance, please don't hesitate to reach out. Happy note-taking!
| Chrome Externsion to quickly jot down what's on your mind | chrome-extension,javascript | 2023-07-29T12:44:41Z | 2024-05-10T18:27:26Z | 2024-05-10T18:27:26Z | 1 | 0 | 14 | 0 | 0 | 4 | null | MIT | JavaScript |
MadobyPy/MadobyWeb | main | <div align="center">
<h1 align="center">Excalith Start Page</h1>
<img src=".github/startpage.gif" />
Thanks "Can Cellek" For this Techy Piece Of Art.
Check out his profile [👉 HERE](https://github.com/excalith)
This is an interactive start page for browsers, inspired from my terminal setup.
[](https://excalith-start-page.vercel.app)
[](https://github.com/excalith/excalith-start-page)
[](https://github.com/excalith/excalith-start-page/pkgs/container/excalith-start-page)
[](https://hub.docker.com/r/excalith/start-page)
</div>
## Demo
You can check the working version from [here](https://excalith-start-page.vercel.app)
> **Warning** This is a demo version and will be updated regularly, which might break your configurations. It is not recommended to use this version for your daily browsing. Please refer to [wiki page](https://github.com/excalith/excalith-start-page/wiki/Getting-Started) for more information.
## Features
- Filter links by typing in the prompt
- Quickly filter links by typing in the prompt. Hitting <kbd>Enter</kbd> will open all filtered links at once
- If nothing filtered, the text in prompt will use the default search engine for searching your input
- Launch websites directly from the prompt. Just type the URL (ie. `github.com`)
- Search websites with custom commands. For example, type `s some weird bug` to search StackOverflow for `some weird bug`
- Wallpaper support through URL with blur and fade effects
- Customizable Fetch UI for fetching browser and system data, including custom image support
- Autosuggest and Autocomplete support just like `zsh` and `fish`
- Cycle through filtered links back and forth
- Multiple theme support (check all [available themes](./public/themes/))
- Built-in configuration editor to easily edit and save your configuration
Please refer to [configuration](https://github.com/excalith/excalith-start-page/wiki/Configuration) page for more information.
### Built-In Commands
- Show usage with `help` command (shows basic usage and your configured search shortcuts)
- Show info with `fetch` command (time, date, system and browser data)
- Update your configuration with `config` command
- `config help` - Displays config command usage
- `config import <url>` - Import configuration from a URL to your local storage
- `config theme` - Lists all [available themes](./public/themes/)
- `config theme <theme-name>` - Switches between themes and sets your local configuration
- `config edit` - Edit local configuration within editor
- `config reset` - Reset your configuration to default
### Key Bindings
- Use <kbd>→</kbd> to auto-complete the suggestion
- Cycle through filtered links using <kbd>TAB</kbd> and <kbd>SHIFT</kbd> + <kbd> TAB</kbd>
- Clear the prompt quickly with <kbd>CTRL</kbd> + <kbd>C</kbd>
- Close windows with <kbd>ESC</kbd>
## Using
There are multiple ways of using this app. Here is a quick preview of them. For more information please refer to [getting started](https://github.com/excalith/excalith-start-page/wiki/Getting-Started) page
### Fork
You can fork this repository and have direct control over the source code. This is the best way to customize the start page to your liking.
1. Fork this repository
2. Modify the `startpage.config.js` for the default configuration
3. If you want, you can change the source code to your like as well (optional)
4. Run `yarn dev` command to test it
5. Host locally, create docker image, or deploy to a server
### Docker
Docker is another convenient way to host the start page. You can either use the image from Docker Hub or Github Registry.
<details>
<summary>Using Docker Registry</summary>
<br>
Pull the latest image
```bash
docker pull excalith/start-page:latest
```
Run the image (change the port mapping of 8080 into something you want)
```bash
docker run --name start-page --restart=always -p 8080:3000 -d excalith/start-page
```
</details>
<details>
<summary>Using Github Registry</summary>
<br>
Pull the latest image
```bash
docker pull ghcr.io/excalith/excalith-start-page:latest
```
Run the image (change the port mapping of 8080 into something you want)
```bash
docker run --name start-page --restart=always -p 8080:3000 -d ghcr.io/excalith/excalith-start-page
```
</details>
### Remote Config Import
If you still prefer to use the online version, I would recommend you to use the remote configuration import feature. This feature allows you to import your configuration from a URL. This way, you will always have a backup file of your configuration. Please refer to [getting started](https://github.com/excalith/excalith-start-page/wiki/Getting-Started) page for more information.
## Customization
You can pretty much customize everything! Please refer to [configuration](https://github.com/excalith/excalith-start-page/wiki/Configuration) and [themes](https://github.com/excalith/excalith-start-page/wiki/Themes) pages for more information regarding themes and configuration options.
## How To Contribute
Please feel free to contribute any way you can. Just keep in mind that you should pay attention to [contributing guideline](.github/CONTRIBUTING.md) before contributing.
## License
The code is available under the [MIT license](LICENSE). Feel free to copy, modify, and distribute the code as you wish, but please keep the original license in the files. Attribution is appreciated and will definetely help improving this project.
| Terminal-inspired, clean, feature-rich and customizable browser start page for geeks. Has built-in editor for customizing. | browser,browser-start-page,customizable,docker,javascript,landing-page,react,terminal-like | 2023-07-25T22:24:23Z | 2023-08-03T11:42:01Z | null | 1 | 0 | 26 | 0 | 0 | 4 | null | MIT | JavaScript |
WaifuAPI/website | production | <div align="center">
<h1 align="center">Waifu.it</h1>
<br />
<img align="center" width="256" height="256" src="https://avatars.githubusercontent.com/u/79479798?s=200&v=4" />
<br />
</div>
<div align="center">
<h3>A Random API Serving Anime Stuffs</h3>
<div align="center">
<img src="https://img.shields.io/github/contributors/WaifuAPI/Waifu.it?color=%236CB4EE" />
<img alt="GitHub issues" src="https://img.shields.io/github/issues/WaifuAPI/Waifu.it?color=%236CB4EE">
<img alt="Bitbucket open pull requests" src="https://img.shields.io/github/issues-pr/WaifuAPI/Waifu.it?color=%236CB4EE">
<img alt="Website" src="https://img.shields.io/website?url=https%3A%2F%2Fwaifu.it">
<img alt="Discord Server" src="https://img.shields.io/discord/479300008118714388?color=%236CB4EE">
</div>
</div>
<hr />
# Contributing
All contributions are greatly appreciated, but I recommend creating an issue or replying in a comment to let me know what you are working on first that way we don't overwrite each other.
Please read [CONTRIBUTING.md](CONTRIBUTING.md) for details on this project.
## Issues
- Feature requests/enhancements
- Bug reports
- Questions/feedback
## Branches
- production -> don't touch, this is what's running in production
- staging -> [pull request][pr] this branch for everything
## Pull Requests
All pull requests are welcome!
- [Fork][fork] the repository on GitHub.
- [Clone][cloning] the forked repo to your local machine.
- Do you changes
- Commit your changes
- Push your changes back up to your fork.
- When you're ready, submit a [pull request][pr] so that we can review your changes.
## Documentation
[DOCS.md](DOCS.md)
[fork]: https://help.github.com/en/articles/fork-a-repo
[cloning]: https://help.github.com/en/articles/cloning-a-repository
[pr]: https://help.github.com/en/articles/about-pull-requests
| 🌸 Next.js repository for waifu.it: Build and maintain the website using Next.js, with a focus on anime content. Anime enthusiasts and developers, this one's for you! 🍃 | anime,api-integration,frontend,javascript,nextjs,nodejs,react,waifu,web-app,website-development | 2023-08-08T11:12:19Z | 2024-04-10T20:33:34Z | 2024-01-10T20:21:25Z | 3 | 8 | 46 | 0 | 1 | 4 | null | AGPL-3.0 | JavaScript |
haardikk21/aiware | main | # A.I.Ware
A CLI-based chatbot that fine-tunes itself in real time by learning from your local Git repo. Ask the chatbot about codebase details for faster development and bug fixes, and have it auto-update on each commit.
## Requirements
- Docker
- Node.js
## Workflow
Install dependencies using `pnpm install`
1. Copy `.env.sample` to `.env`
1.1. Specify `OPENAI_API_KEY` and `DEFAULT_REPO_PATH` in the `.env`
2. Start a new Postgres database locally using `pnpm db:up` which will also install the `pgvector` extension.
3. Run `pnpm db:push` to sync the schema with your database
4. Run `pnpm dev` to start the CLI
Once started:
1. Provide a repo path if different from `DEFAULT_REPO_PATH` - else leave empty
2. If the repo is new, it will embed the codebase into Postgres using OpenAI Embeddings
3. Ask questions about your codebase in the chatbot
4. A.I.Ware will check for new commits to delete old embeddings of changed files and re-embed them periodically so it always has the latest context.
## License
This repo is licensed under the [MIT License](./LICENSE).
| A CLI-based chatbot that fine-tunes itself in real time by learning from your local Git repo. Ask the chatbot about codebase details for faster development and bug fixes, and have it auto-update on each commit. | chatbot,gpt,javascript,langchain,open-ai,openai,prisma,with-prisma,with-vectorstores | 2023-08-01T20:05:33Z | 2023-08-08T16:01:32Z | null | 1 | 1 | 6 | 0 | 2 | 4 | null | MIT | TypeScript |
mohansahu18/study-notion- | main | # Study Notion Fullstack project LMS
Study Notion is an ED Tech (Education Technology) web application developed using the MERN stack.
---
## Features
- User Authentication: Study Notion provides secure user registration and authentication using JWT (JSON Web Tokens). Users can sign up, log in, and manage their
profiles with ease.
- Courses and Lessons: Instructors can create and edit created courses. Students can enroll in courses, access course materials, and track their progress.
- Progress Tracking: Study Notion allows students to track their progress in enrolled courses. They can view completed lessons, scores on quizzes and
assignments, and overall course progress.
- Payment Integration: Study Notion integrates with Razorpay for payment processing. Users can make secure payments for course enrollment and other services
using various payment methods supported by Razorpay.
- Search Functionality: Users can easily search for courses, lessons, and resources using the built-in search feature. This makes it convenient to find relevant
content quickly.
- Instructor Dashboard: Instructors have access to a comprehensive dashboard to view information about their courses, students, and income. The
dashboard provides charts and visualizations to present data clearly and intuitively. Instructors can monitor the total number of students enrolled in
each course, track course performance, and view their income generated from course sales.
---
***
# DEMO VIDEO
https://github.com/mohansahu18/study-notion-/assets/123477420/2ce5ecf2-b7a1-4a5b-91ef-70ec29d6fff2
# Screenshots
# Screenshots Of Student Dashboard
# Screenshots Of Instructor Dashboard
***
| This MERN project, styled with Tailwind CSS, serves as a responsive Learning Management System. Instructors manage courses, while users access registration, login, and password reset. Features include routing, Redux state management, JWT security, Razorpay integration, email notifications, React Hook Form, ChartJS data visualization, animations . | backend,css3,expressjs,frontend,full-stack,html5,javascript,mern-stack,mongodb,mongoose | 2023-07-21T13:21:51Z | 2023-08-31T19:22:41Z | null | 1 | 0 | 121 | 1 | 0 | 4 | null | null | JavaScript |
BjoernRave/i18n-magic | master | # i18n Magic
Your CLI toolkit to help you with managing your translations in your project.
This currently only works for JSON based translation systems, like: [Next-Translate](https://github.com/aralroca/next-translate)
To use:
1. Create a `OPENAI_API_KEY` in your `.env` file
2. Create a config file, called `i18n-magic.js` in your project root.
The content of the file should look something like this:
```js
module.exports = {
globPatterns: ['./components/**/*.tsx', './pages/**/*.tsx', './lib/**/*.ts'],
loadPath: 'locales/{{lng}}/{{ns}}.json',
savePath: 'locales/{{lng}}/{{ns}}.json',
locales: ['en', 'de'],
defaultLocale: 'de',
defaultNamespace: 'common',
namespaces: ['common', 'forms'],
context:
'This is a context which increases the quality of the translations by giving context to the LLM',
};
```
then just run:
```bash
npx i18n-magic [command]
```
`scan`
Scan for missing translations, get prompted for each, translate it to the other locales and save it to the JSON file.
`replace`
Replace a translation based on the key, and translate it to the other locales and save it to the JSON file.
`check-missing`
Checks if there are any missing translations. Useful for CI/CD or for a husky hook
| CLI to help you manage your locales JSON with translations, replacements, etc. with GPT 3.5 | i18n,javascript,locales-translation,openai | 2023-07-22T13:56:54Z | 2024-02-20T18:37:12Z | null | 1 | 0 | 11 | 0 | 0 | 4 | null | null | TypeScript |
AndiSyarif/crud-laravel-10-serverside | main | # Andis Dev
## _Turorial CRUD Laravel 10 Datatable Server Side_
## Features
- CRUD Laravel 10 Server Side
- Validation
- Sweat Alert
- Datatable Server Side
- Javascript Validation
- FontAwesome 6
## Required
- Laravel 10
- PHP newer version
- Composer
- Datatable
- Sweetalert
- Javascript
- FontAwesome 6
- Server Xampp/Laragon
## Installation
Download or clone source code <br>
create database laravel
Install the dependencies and start the server.
run composer update <br>
run php artisan migrate:fresh -seed <br>
run php artisan serve <br>
open link at your browser
http://127.0.0.1:8000
## Demo Link
https://crud-serverside.andisdev.tech/
## Screenshoot
## License
Andis Dev
**Free for learn !**
| Tutorial CRUD Laravel 10 Datatable Server Side | alert,crud,datatables-serverside,font-awesome,javascript,laravel,php8,tutorial,validation | 2023-08-01T07:40:25Z | 2023-08-06T23:31:37Z | null | 2 | 0 | 9 | 0 | 0 | 4 | null | null | JavaScript |
tobyyosoba777/My-JavaScript-Journey | main | null | Documentation of my journey to javaScript mastery | es6,javascript,javascript-es6,vanilla-javascript | 2023-08-04T01:57:01Z | 2024-05-17T17:01:13Z | null | 1 | 0 | 774 | 0 | 0 | 4 | null | null | JavaScript |
VarshaRani9/FOOD_ORDERING_APP | main | null | A food ordering app (SWIGGY CLONE) meticulously designed with HTML, JavaScript, ReactJs, Redux, and elevated by the sleekness of Tailwind CSS. | api,javascript,reactjs,redux-toolkit,tailwindcss | 2023-07-21T13:57:34Z | 2023-07-22T03:59:38Z | null | 1 | 0 | 5 | 0 | 0 | 4 | null | null | JavaScript |
emmanuelonah/core-oop-in-js | master | # Core OOP in JavaScript - 1st Edition
This eBook dive deep into JavaScript es5 Object Oriented Programming(i.e before the invention of the es6 syntactic "class"), this will help you understand the internal mechanism of everything being an object in JavaScript. This is the **first edition** of the eBook:
<a href="https://github.com/emmanuelonah/core-oop-in-js"><img src="./public/book-cover.png" alt="Core OOP in Js" width="75"></a>
**To read more about the motivations and perspective behind this eBook, check out the [Preface](preface.md).**
## Table of content
* [Introduction](./introduction/README.md)
* [Constructor](./constructor/README.md)
* [Instantiation](./instantiation/README.md)
* [Four Pillars of OOP](./pillars-of-oop/README.md)
* [Bonus](./bonus/README.md)
## Contributions
Please feel free to contribute to the quality of this content by submitting PRs for improvements to code snippets, explanations, etc.
Any contributions you make to this effort **are of course greatly appreciated**.
But **PLEASE** read the [Contributions Guidelines](CONTRIBUTING.md) carefully before submitting a PR.
----
## License & Copyright
<a href="https://www.linkedin.com/in/onah/"><img src="./public/author.png" alt="Author: Emmanuel Onah" width="75"></a>
The materials herein are all © 2021 - 2023 Emmanuel Onah.
<a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/"><img alt="Creative Commons License" style="border-width:0" src="https://i.creativecommons.org/l/by-nc-nd/4.0/88x31.png" /></a><br />This work is licensed under a <a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">Creative Commons Attribution-NonCommercial-NoDerivs 4.0 Unported License</a>.
| An eBook on Core OOP in JavaScript(es5) 📘. | book-series,es2015,es5,es5-javascript,javascript,mixins,oop,oop-principles,prototype,teaching | 2023-07-29T10:43:42Z | 2023-08-04T00:41:20Z | null | 1 | 0 | 3 | 0 | 0 | 4 | null | NOASSERTION | null |
mayerprog/routine-app-ui-bll | main | <h1 align='center'>Routine App - UI Overview</h1>
<div align='center'>
<img width='200px' src='/.github/photo_2_2023-12-11_21-13-55.jpg' alt='scr1'>
<img width='200px' src='/.github/photo_1_2023-12-11_21-13-55.jpg' alt='scr2'>
<img width='200px' src='/.github/photo_9_2023-12-11_21-13-55.jpg' alt='scr3'>
<img width='200px' src='/.github/photo_2023-12-11_21-16-53.jpg' alt='scr3'>
<img width='200px' src='/.github/photo_2023-12-11_21-23-11.jpg' alt='scr3'>
<img width='200px' src='/.github/photo_3_2023-12-11_21-13-55.jpg' alt='scr3'>
<img width='200px' src='/.github/photo_5_2023-12-11_21-13-55.jpg' alt='scr3'>
<img width='200px' src='/.github/photo_2024-01-09_20-29-45.jpg' alt='scr3'>
<img width='200px' src='/.github/photo_4_2023-12-11_21-13-55.jpg' alt='scr3'>
<img width='200px' src='/.github/photo_7_2023-12-11_21-13-55.jpg' alt='scr3'>
<img width='200px' src='/.github/photo_8_2023-12-11_21-13-55.jpg' alt='scr3'>
<img width='200px' src='/.github/photo_2023-12-12_09-51-59.jpg' alt='scr3'>
</div>
# Description
Routine App UI combines the power of React Native and Redux, with help of a robust back-end it delivers a seamless task management experience. Users can create, customize, and schedule tasks with rich media attachments and flexible reminders. The upcoming features will introduce social media logins, enhanced notification flexibility, and document support, making Routine App an even more versatile tool for personal organization and productivity.
### **Existing Features**
- #### **User Authentication**
- #### **Task Creation**
- #### **Media and Links Integration**
- #### **Task Notification Scheduling**
- #### **Task Modification (update or delete tasks)**
### **Upcoming Features**
- #### **Social Media Authorization**
- #### **Flexible Notification Settings (receive notifications daily, weekly, or on chosen weekdays)**
- #### **Document Support**
- #### **Integrated Calendar View**
- #### **Social Sharing (сonnect and share daily routines directly with friends on Facebook)**
> The app can be run only on iOS
# Get Started
To run this web app you need (if not installed yet):
- [NodeJS](https://nodejs.org/en/)
- [Yarn](https://yarnpkg.com/)
- [Expo](https://docs.expo.dev/get-started/installation/)
Then:
- Clone the repository with `git clone https://github.com/mayerprog/routine-app-ui-bll`
- Install dependencies `yarn install`
- Run `yarn start` to run the project on Expo Go app
> If you want to run it on your phone, you need to install `Expo Go`, which you can find on `App Store`.
## Tecnologies
- React Native
- Expo
- Redux
- Redux Toolkit
- Expo Notifications
- React Native Reanimated
- React Native Gesture Handler
- CSS Flexbox
## Design
You can find the [figma design here](https://www.figma.com/file/ZCyuMsuoshICM0soWSnqaM/routine-app?type=design&node-id=33-589&mode=design&t=EKrzSEqfcvplYUxu-0)
## API
You can find my [server code here](https://github.com/mayerprog/routine-app-api)
## Contacts
<p>Mayra Tulegenova</p>
- Telegram: [mayerprog](https://t.me/mayerprog)
- Email: [supermayerehs@gmail.com](supermayerehs@gmail.com)
| RoutineAppUI - application that helps keep your routine | expo,expo-go,ios,javascript,react,react-native,reactjs | 2023-07-25T15:27:10Z | 2024-02-12T19:45:12Z | null | 1 | 0 | 135 | 0 | 0 | 4 | null | null | JavaScript |
qiyunblog/qiyunblog-api | main | # qiyunblog-api
(山河)shanhe和(小乌龟)共同开发的一个基于时下流行的SpringBoot+Mybatis前后端分离技术的现代个人博客
本项目作为我们的第一个项目，我们会尽量每天更新,保证每周进行更新。<br>
项目基于MIT协议开源，欢迎大家使用我们的代码，也欢迎大家基于我们的代码提交分支。
基于这套后端可以进行WEB,小程序，APP等多端开发，实现了一次开发，多端能重复使用。
项目技术以及项目运行的注意事项在文档下方
### 项目技术一览
本项目使用到的技术有:<br>
应用层:Spring,SpringBoot,Swagger,Lombok,JWT <br>
网关层:Nginx,Tomcat<br>
用户层:HTML5,CSS3,Javascript,Jquery,Ajax,layUI<br>
数据层:MySql,Mybatis<br>
管理工具:Maven<br>
本来想用基于Vue脚手架,然后使用ElementUI的,但是奈何实力不精,放弃了.
### 项目运行注意事项
#### 运行环境
Tomcat 8 以上,10以下<br>
Springboot 2.7<br>
MySQL 5.7<br>
Java JDK 11<br>
Maven 3.6
#### 注意事项
请注意修改在 resources 目录下的项目配置文件和端口号
### API接口
本项目基于Spring Doc库来构建API文档，
项目运行之后打开/Doc.html 就是API文档
### 数据库设计
关于数据库E-R图我们会在项目完结时公布。
### 鸣谢
layUI 后台使用了LayUI
| 七云博客，一个基于SpringBoot+Mybatis前后端分离的个人博客 | ajax,axios,css,html,java,javaee,javascript,jquery,jwt,lombok | 2023-07-21T10:28:34Z | 2023-09-25T13:52:51Z | null | 2 | 0 | 48 | 0 | 0 | 4 | null | MIT | CSS |
4lador/11ty-tailscript | main | # Tailscript - An Eleventy (11ty) Starter
Hello, I am a minimalist starter project that glues together:
- <a href="https://www.11ty.dev" target="blank">Eleventy (11ty)</a>
- <a href="https://www.typescriptlang.org" target="blank">Typescript</a>
- <a href="https://tailwindcss.com" target="blank">Tailwind</a>
- <a href="https://postcss.org" target="blank">PostCSS (nesting, imports, media queries, minify)</a>
- <a href="https://fontawesome.com" target="blank">Fontawesome</a>
- <a href="https://github.com/11ty/webc" target="blank">WebC</a>
- <a href="https://webpack.js.org" target="blank">Webpack</a>
- <a href="https://vitejs.dev" target="blank">Vite</a>
- <a href="https://decapcms.org" target="blank">Decap CMS</a>
Feel free to use and improve me without limitations :)
## Documentation and Demo
I got my own demo website that features my documentation, if you want to check it out.
<a href="https://vocal-licorice-a3b377.netlify.app" target="_blank">Demo & Documentation</a>
## Lighthouse
I got 100 everywhere in Lighthouse so i'm born optimized !
<a href="https://pagespeed.web.dev/analysis/https-vocal-licorice-a3b377-netlify-app/hecgcxec10?form_factor=desktop" target="_blank">Google Pagespeed Insight</a>
| (WIP) Eleventy starter that use Typescript, PostCSS, Tailwind, WebC, Fontawesome, Decap CMS, Webpack ready and Typescript | decap-cms,eleventy,jamstack,javascript,typescript | 2023-07-21T21:38:55Z | 2023-10-15T02:06:26Z | null | 1 | 12 | 60 | 0 | 0 | 4 | null | MIT | JavaScript |
yarin-zhang/MarkdownSticky | main | # Markdown Sticky (Markdown 便利贴)
[](https://opensource.org/licenses/MIT)
[](https://github.com/your-username/your-repo)
[](https://github.com/your-username/your-repo)
[](https://github.com/your-username/your-repo)
Markdown Sticky is a simple, self-hosted, single-page note-taking application that allows users to write notes in Markdown and store them in the browser's local storage. It's designed to be as simple as possible, with no user authentication required. You can download the repository from GitHub and start using it by opening the `index.html` file in your browser.
Markdown Sticky 是一个简单的、可本地部署、单页面记事应用，允许用户以 Markdown 格式编写便签，并将它们存储在浏览器的本地存储中。它的设计尽可能简单，无需用户认证。你可以从 GitHub 下载仓库，然后通过在浏览器中打开 `index.html` 文件来开始使用。
<img width="1432" alt="image" src="https://github.com/yarin-zhang/MarkdownSticky/assets/58888890/82be41b9-edf8-44e1-a540-dee0c92b119c">
## Demo
[🔗 MarkdownSticky Demo](https://lab.utgd.net/MarkdownSticky/)
## Features (特性)
- Write notes in Markdown (用 Markdown 编写便签)
- Drag and drop notes anywhere on the page (在页面上任意拖放便签)
- Resize notes (调整便签大小)
- Save notes in the browser's local storage (在浏览器的本地存储中保存便签)
- Import and export notes in JSON format (以 JSON 格式导入和导出便签)
## Advantages (优点)
- Simple and lightweight (简单轻量)
- No internet connection required (无需网络连接)
- No user authentication required (无需用户认证)
## Disadvantages (缺点)
- Notes are not synced across devices (便签不会在设备间同步)
- Notes are lost if the browser's local storage is cleared (如果清除浏览器的本地存储，便签将会丢失)
## Usage (使用方法)
1. Download the repository from GitHub (从 GitHub 下载仓库)
2. Open the `index.html` file in your browser (在浏览器中打开 `index.html` 文件)
3. Start writing notes! (开始编写便签！)
## License (许可证)
MIT
## Author (作者)
Yarin Zhang
Power By GPT-4
| Markdown Sticky 一个简单的单页面记事应用，你可以下载到本地使用。Markdown Notes is a simple, single-page note-taking application. | javascript,pwa,self-hosted | 2023-08-02T03:20:42Z | 2023-08-25T01:07:05Z | 2023-08-02T08:21:23Z | 2 | 3 | 19 | 0 | 1 | 4 | null | null | JavaScript |
Mohammad-Abohasan/Mastering-JavaScript-in-20-Days | master | # Gaza Sky Geeks Learning Sprint - 20-Day Learning JavaScript Challenge
Welcome to the 20-Day Learning JavaScript Challenge! 🚀
In this challenge, you will enhance your JavaScript skills and knowledge. Each day, you will explore different aspects of JavaScript, building a solid foundation and gaining hands-on experience through practical exercises and projects.
## Overview
- **Duration:** 20 days.
- **Objective:** Improve JavaScript proficiency through daily learning and practice.
## Courses
- [JavaScript: From First Steps to Professional](https://frontendmasters.com/courses/javascript-first-steps/)
- [JavaScript: The Hard Parts, v2](https://frontendmasters.com/courses/javascript-hard-parts-v2/)
- [Deep JavaScript Foundations, v3](https://frontendmasters.com/courses/deep-javascript-v3/)
## Coding Challenges
💡 [freeCodeCamp: **Mohammad-Abohasan**](https://www.freecodecamp.org/Mohammad-Abohasan)
## Daily Learning Process
1. Each day, you will watch a portion of the above-mentioned assigned courses.
2. Solve all the JavaScript coding challenges that will be provided by the GSG team.
3. Summarize your daily learning and document your challenge solutions on a separate readme page.
4. Repeat the process for the next 20 days, gradually advancing your JavaScript skills.
## Guidelines
- Commit to a consistent schedule and allocate sufficient time each day to complete the learning activities.
- Take notes, document your progress, and maintain a personal learning log throughout the challenge.
- Experiment, explore, and don't be afraid to make mistakes. Learning comes from both successes and failures.
- Engage with the other GSG trainees. Seek support, share insights, and collaborate with fellow learners using the dedicated discussion telegram channel.
- Celebrate your achievements and reflect on your growth throughout the challenge.
## Folder Structure
📍 [**Course 1**](https://github.com/Mohammad-Abohasan/Mastering-JavaScript-in-20-Days/blob/master/Course01.md)
<br />
📍 [**Course 2**](https://github.com/Mohammad-Abohasan/Mastering-JavaScript-in-20-Days/blob/master/Course02.md)
<br />
📍 [**Course 3**](https://github.com/Mohammad-Abohasan/Mastering-JavaScript-in-20-Days/blob/master/Course03.md)
| null | javascript | 2023-08-04T17:02:13Z | 2023-09-21T17:49:04Z | null | 1 | 37 | 100 | 1 | 0 | 4 | null | MIT | HTML |
shawonk007/learnopia-lms | master | # Learnopia - Learning Management System (LMS)
Welcome to **Learnopia**, an Learning Management System (LMS) built using **[Laravel](https://laravel.com/)** Blade, **[Bootstrap 5](https://getbootstrap.com/)** and other related tools. **Learnopia** is designed to provide a robust platform for managing and delivering online courses and educational content. This `README` file will guide you through the installation process, usage, important commands used in the project, and additional resources used, such as the **[AdminKit](https://adminkit.io/)** Admin panel.
# Table of Contents
- [Introduction](#introduction)
- [Technologies Used](#technologies-used)
- [Getting Started](#getting-started)
- [Prerequisites](#prerequisites)
- [Installation](#installation)
- [Usage](#usage)
- [Admin Dashboard](#1-admin-dashboard)
- [Managing Courses](#2-managing-courses)
- [Enrolling Students](#3-enrolling-students)
- [Managing Instructors](#4-managing-instructors)
- [Student Progress Tracking](#5-student-progress-tracking)
- [Reporting and Analytics](#6-reporting-and-analytics)
- [AdminKit Admin Panel](#adminkit-admin-panel)
- [Contributing](#contributing)
- [License](#license)
## Introduction
Learnopia is an LMS developed using Laravel Blade, a powerful template engine provided by the Laravel framework. The system aims to facilitate e-learning by providing essential features for administrators, instructors, and learners. From creating and managing courses to tracking student progress, Learnopia empowers educational institutions and organizations to deliver a seamless learning experience.
## Technologies Used
The following technologies have been used in the development of Learnopia:
- **[Laravel](https://laravel.com/)** : A popular PHP web application framework known for its elegant syntax and feature-rich ecosystem.
- **[Laravel Blade](https://laravel.com/)** : The templating engine provided by Laravel for designing and rendering views.
- **[MySQL]** : The database management system used to store application data.
- **[Bootstrap](https://getbootstrap.com/)** : A CSS framework for creating responsive and attractive UI components.
- **[FontAwesome](https://fontawesome.com/)**: A popular icon library that provides a wide range of icons for web projects.
## Getting Started
Follow these instructions to get a copy of the Learnopia project up and running on your local machine for development and testing purposes.
#### Prerequisites
Before you proceed, ensure you have the following software installed:
- PHP (Version 8.2)
- Composer (Version 2.5)
- MySQL (Version 8.2)
- Laravel (Version 10.16)
#### Installation
1. Clone the **Learnopia** repository to your local machine using the following command:
```bash
git clone https://github.com/shawonk007/learnopia-lms.git
```
2. Navigate to the project directory:
```bash
cd learnopia-lms
```
3. Install the required `PHP` dependencies using Composer:
```bash
composer install
```
4. Install `Node.js` dependencies
###### Using npm:
```bash
npm install
```
or,
###### using Yarn:
```bash
yarn
```
5. Generate `Vite` serve manifest:
###### Using npm:
```bash
npm run dev
```
or,
###### using Yarn:
```bash
yarn dev
```
6. Create a new MySQL database for Learnopia and update the `.env` file with your database credentials:
```bash
cp .env.example .env
```
7. Generate a unique application key:
```bash
php artisan key:generate
```
8. Run the database migrations and seed the database with initial data:
```bash
php artisan migrate --seed
```
9. Start the development server:
```bash
php artisan serve
```
Congratulations! Learnopia should now be up and running at `http://localhost:8000`.
## Usage
Learnopia provides a user-friendly and intuitive interface for managing all aspects of your e-learning platform. Below are some key features and functionalities along with usage instructions:
#### 01. Admin Dashboard
Upon logging in as an administrator, you will be greeted with the Admin Dashboard. The dashboard offers an overview of key statistics, such as the total number of registered users, enrolled courses, and recent activity. It provides quick access to essential sections of the LMS, allowing you to manage courses, instructors, and students efficiently.
#### 02. Managing Courses
As an administrator or instructor, you can easily create, edit, and manage courses. To create a new course, navigate to the "Courses" section and click on "Create Course." Fill in the course details, such as the title, description, duration, and associated instructor. You can also upload course materials, including video lectures, presentations, and assignments.
#### 03. Enrolling Students
Students can enroll in courses by browsing the course catalog or searching for specific courses. Once a student finds a course of interest, they can click on the "Enroll" button to join the course. As an administrator or instructor, you can view the list of enrolled students for each course and track their progress.
#### 04. Managing Instructors
Learnopia allows administrators to manage instructors easily. You can add new instructors, view existing ones, and edit their profiles. Instructors play a crucial role in delivering high-quality educational content, and the LMS provides them with the necessary tools to create engaging courses.
#### 05. Student Progress Tracking
The LMS enables instructors and administrators to track the progress of students enrolled in each course. You can view individual student performance, monitor completed assignments, and assess quiz scores. This feature helps in identifying students who may need additional support or intervention.
#### 06. Reporting and Analytics
Learnopia provides comprehensive reporting and analytics features. As an administrator, you can generate reports on course performance, user activity, and overall system usage. These insights can aid in making data-driven decisions to enhance the learning experience.
## AdminKit Admin Panel
Learnopia incorporates the AdminKit Admin Panel to streamline administrative tasks. AdminKit is a flexible and modern admin dashboard template built with Bootstrap and other front-end technologies. Its customizable components and UI elements enable efficient management of various LMS functionalities.
Get it from here: **[AdminKit](https://adminkit.io/)**
## License
Learnopia is distributed under the `GNU General Public License version 3.0 (GPL-3.0)`. You can find the full text of the license in the `LICENSE` file. | Learnopia: An LMS powered by Laravel Blade, facilitating e-learning with essential features for admins, instructors, and learners. Manage courses, track progress, and ensure a seamless learning experience. Empowering institutions for better education. | blade,css,css3,database,html,html5,javascript,laravel,laravel-framework,mariadb | 2023-07-29T11:51:43Z | 2023-12-07T11:33:47Z | null | 1 | 0 | 31 | 0 | 2 | 4 | null | GPL-3.0 | JavaScript |
Alok-2002/Tribute_Page_For_Atal_Bihar_Vajpaayee | main | # Tribute Page for Atal Bihari Vajpayee
This repository contains a tribute page dedicated to the great Indian statesman and former Prime Minister, Atal Bihari Vajpayee. The page is built using HTML, CSS, and JavaScript to showcase his life, achievements, and contributions to the nation.
## Live Demo
Check out the live demo of the Tribute Page at: [Tribute Page](https://atal-bihari-vajpaayee.vercel.app)
## Table of Contents
- [Introduction](#introduction)
- [Features](#features)
- [Installation](#installation)
- [Usage](#usage)
- [Contributing](#contributing)
- [License](#license)
## Introduction
Atal Bihari Vajpayee was a prominent Indian politician, poet, and visionary leader who served as the Prime Minister of India three times. This tribute page aims to honor his life and work, highlighting some of the key moments and achievements that shaped India's destiny during his tenure.
## Features
- Responsive design for seamless viewing on various devices
- Sections dedicated to different aspects of Atal Bihari Vajpayee's life
- Interactive elements powered by JavaScript to enhance user experience
- Stylish and visually appealing CSS to complement the content
## Installation
To run this project locally on your machine, follow these steps:
1. Clone the repository to your local machine using the following command:
```
git clone https://github.com/alok-2002/Tribute_Page_For_Atal_Bihar_Vajpaayee.git
```
2. Navigate to the project directory:
```
cd Tribute_Page_For_Atal_Bihar_Vajpaayee
```
3. Open the `index.html` file in your preferred web browser.
## Usage
Feel free to explore the tribute page to learn more about the life and achievements of Atal Bihari Vajpayee. The page is designed to be intuitive and user-friendly, providing a glimpse into the remarkable journey of this influential leader.
## Contributing
If you wish to contribute to this tribute page or have any suggestions for improvements, please follow these steps:
1. Fork the repository.
2. Create a new branch for your feature/fix:
```
git checkout -b feature/your-feature-name
```
3. Make the necessary changes and commit them:
```
git commit -m "Add your commit message here"
```
4. Push your changes to your forked repository:
```
git push origin feature/your-feature-name
```
5. Open a pull request, explaining the changes you've made and their significance.
## License
This project is licensed under the [MIT License](https://opensource.org/licenses/MIT) - see the [LICENSE](LICENSE) file for more details.
| This repository contains a tribute page dedicated to the great Indian statesman and former Prime Minister, Atal Bihari Vajpayee. The page is built using HTML, CSS, and JavaScript to showcase his life, achievements, and contributions to the nation | css,css3,html,javascript,alok,alok-2002,alok-sharma,cdn,git,github | 2023-07-27T05:38:30Z | 2023-07-27T12:04:54Z | null | 1 | 0 | 14 | 0 | 0 | 4 | null | MIT | HTML |
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