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C_sharp : I have in xaml : And here is screenshot ( using magnifier ) : My question is what is going on here ? Why tooltip displays value differently ( decimal point is . while , is expected ) ? Longer story : I am trying to display numbers in same format as in user Windows number format preferences.For this I 've over...
Tooltip culture is wrong
C_sharp : I try to find some information about method overloading resolution in case of presence of user-defined implicit conversions and about conversions priority.This code : Produces output : So , It looks like compiler chosen user-defined conversion instead of built-in implicit conversion from int to double ( built...
C # Method overloading resolution and user-defined implicit conversions
C_sharp : Lets assume , we have an operation based on some file , connection , or other resource.We need a method , which can be run with provided resource , or - if not provided - creates own : } It works , but this is really ugly for me.Is it a way to write it in more compact and `` nice '' way ? I can not use : as i...
C # conditional using and default parameter
C_sharp : I need a PHP version of the following C # code : ... this code snippet appears to be incomplete . But here 's what I think is going on : concatenating dateSince , siteID , and sharedSecret . Stealing underpants. ? ? ? converting that string into a ascii encoded byte array.taking the MD5 hash of that array.Thi...
How would I translate this C # code into PHP ?
C_sharp : I have a Linq query with a select , from my Linq query provider it I get an expression tree containing a MethodCallExpression , but just how can I get the select projections from the MethodCallExpression ? Query may look like : <code> internal static object Execute ( Expression expression , bool isEnumerable ...
Getting projections from MethodCallExpression
C_sharp : I am creating a console application for the purpose of learning the state and observer patterns . The program is based on a basic order system whereby each order can have a state ( pending , ready , submitted i.e state pattern ) and subscribers that are interested in receiving notifications from the order whe...
Should these interfaces be inherited at interface level or implemented at class level ?
C_sharp : Imagine this C # code in some method : Let 's say no one is using any explicit memory barriers or locking to access the dictionary . If no optimization takes place , then the global dictionary should be either null ( initial value ) or a properly constructed dictionary with one entry.The question is : Can the...
Can another thread see partially created collection when using collection initializer ?
C_sharp : So I made myself a C # -WebApi REST Service.When I build/run my application in Visual Studio everything works perfectly.But everytime I try to publish my project as a filesystem , two errors appear in the error list . The strange thing here is that these errors disappear after a few seconds and no errors are ...
Visual Studio 2013 publishing fails and reports `` non-existing '' error
C_sharp : please look at the below code : and the result is : FalseTrueand now consider this one : and the result is : TrueTrue “ == ” compares if the object references are same while “ .Equals ( ) ” compares if the contents are same . and i want to know what is different between these codes ? ! and both of them turn o...
`` stringDemo '' versus new string ( `` stringDemo '' .ToCharArray ) ;
C_sharp : 2nd edit : I think my original test script has an issue , the 10000000 times loop is , in fact , dealing with the same memory location of an array , which makes the unsafe version ( provided by Marc here ) much faster than bitwise version . I wrote another test script , I noticed that bitwise and unsafe offer...
C # Signed & Unsigned Integral to Big Endian Byte Array , and vice versa using Bitwise way with `` best '' performance
C_sharp : I have a .NET Console App integrated with Entity Framework and Discord Sharp Plus with the following libraries : DSharpPlusDSharpPlus.CommandsNextMicrosoft.EntityFrameworkCore.DesignMicrosoft.EntityFrameworkCore.SqliteMicrosoft.EntityFrameworkCore.ToolsRunning the application without debugging ( Control + F5 ...
.NET Console App with Entity Framework Core : 'The process has no package identity ' only when started without debugging
C_sharp : On my ASPX page I 've added Dropdownlist.Elements in this list are divided to groups by adding disabled list items : Those list items are grayed , I ca n't select it by mouse or by clicking cursor arrows ( up/down ) .That is correct.But problem is , that after clicking '- ' key this list item is selected . I ...
Error in Dropdownlist
C_sharp : I 've written two LINQ queries using the join method . Essentially , if I switch the order of the objects to be joined , the query no longer works and throws the error : '' Unable to create a constant value of type 'Domain.Entities.UsersSitesRole ' . Only primitive types ( 'such as Int32 , String , and Guid '...
Why does this LINQ join query work , but this other one does n't ?
C_sharp : I have the following code : This is a modified example from CLR via C # 4th ed ( pg 138 ) .In the book it says thatwill output `` ( 2 , 2 ) '' because the boxed p will be immediately garbage collected.However , would n't the actual reason for this be the fact that changing the value of a boxed variable only c...
Changing a struct after boxing it
C_sharp : I am trying to read foreign characters from an .ini file.This is the method I am usingI am using Encoding.ASCII but apparently GetPrivateProfileString is n't . The bytes coming out of it need encoding probably . How can I do that ? Edit : ExampleThis will print : Tavar ? instead of Tavaré <code> [ DllImport (...
File read foreign characters
C_sharp : Are there any C # specifications that state how implicit conversions of terms of integral types ( e.g. , int ) to terms of double are supposed to work ? If so , can someone tell me the algorithm or direct me to it ? C # 6.0 draft specification states “ the value of a real literal of type float or double is de...
How does C # implicitly cast terms of integral types to terms of double ?
C_sharp : My class has a method which produces a Task < int > object using a TaskCompletionSource < int > . Then it does some asynchronous operations and sets the result . I need to know whether I can trust the task 's ContinueWith method or not : Can the caller of CalculateAsync method do something with the produced t...
How to cancel a task 's continuation ?
C_sharp : I am currently cleaning up some of our legacy code base in which we make use of extern methods . The parameter names are all over the place in terms of naming conventions . I 'd like to consolidate them.ExampleCan I safely rename new_status to newStatus or will that break the contract ? ReSharper suggests it ...
Is it safe to rename extern method parameters in C # ?
C_sharp : Does there exist a standard pattern for yield returning all the items within an Enumerable ? More often than I like I find some of my code reflecting the following pattern : The explicit usage of a foreach loop solely to return the results of an Enumerable reeks of code smell to me . Obviously I could abandon...
What is the proper pattern for handling Enumerable objects with a yield return ?
C_sharp : I want to know is there a better/easier way to load users by birthday.I have a User instance , which has properties , including this one : public DateTime ? BirthDate { get ; set ; } What I want to do is to load that users who has bdays from one date to another : I do n't care about birthday year , for exampl...
Load users by birthday
C_sharp : I 'm experimenting with switch statement pattern matching , and I 'm looking for a way to return false if either value in a two value tuple is zero . This is the code I 'm trying : In VSCode 1.47 and dotnetcore 3.14 I get a compile-time error : CS8652 : The feature 'type pattern ' is in Preview ` What is the ...
How to use C # pattern matching with tuples
C_sharp : I was wondering how could I use a custom object in more than one panel.I made a panelModified object ( extends from Panel ) and want to place it in two normal panels , so when the object change its status , both panels display the updated information.In my case the `` panelModified '' is a panel with some But...
How can I show an object in multiple panels ?
C_sharp : I have a class of this type : But sometimes I need to use this class as a non generic class , ie the type TResult is void.I ca n't instantiate the class in the following way : Also , I 'd rather not specify the type omitting the angle brackets : I do n't want re-write the whole class because it does the same ...
What if T is void in Generics ? How to omit angle brackets
C_sharp : I stumbled across this article and found it very interesting , so I ran some tests on my own : Test One : Outputs : Test Two : Outputs : According to the article , in Test One all of the lambdas contain a reference to i which causes them to all output 5 . Does that mean I get the expected results in Test Two ...
odd lambda behavior
C_sharp : I 'm trying to connect Chrome extension and my C # application.I 'm using this code https : //stackoverflow.com/a/13953481/3828636Everything is almost working there in only one problem I can send message only 6 times and than my c # app does n't recieve anything . When I re-open my extension ( click on icon )...
Communication JQuery and C #
C_sharp : Executing a UWP application in DEBUG works perfectly.Using exactly the same code compiled in RELEASE crashes with this error message when executing this code ( it 's using Dapper 1.5.1 and System.Data.SQLite 1.0.109.2 ) The application is UWP configured as below . Furthermore , the faulting code is a .NET Sta...
PlatformNotSupportedException throws when using Dapper with WP
C_sharp : I 'm trying to debug ( hit breakpoint ) a python script which is executed through a new process from C # .I have installed Child Process Debugging Power tool as that tool supposedly allows one to do that.According to its documentation it requires two things : The parent process must be debugged with the nativ...
Mixed mode Debugging Python/C # using Child Process Debugging Power Tool
C_sharp : ** I have 36 of these case statements each one for another for a different picture box ; how do I group them all into one case statement so my code can be more efficient** <code> private void makeMoleVisable ( int mole , PictureBox MoleHill ) { switch ( mole ) { case 1 : if ( p01.Image == pmiss.Image & & Mole...
How do I merge all the cases into One ?
C_sharp : The following code works if Cassandra and the code are on the same machine : Assuming a username and password is needed if the code is on one machine and cassandra is on a different machine ( different ip address ) ? So I have tried : I get the following error message : The iptables on the node ( the cassandr...
How do I connect to a Cassandra VM
C_sharp : I have set up a VirtualPathProvider and it is working fine for direct url calls like http : // ... /home/index in the address bar.However , I would like this to work for the Html helper too , but right now it is ignoring the VirtualPathProvider for the html helper calls in the view : Is there a way to solve t...
Html helper does not use custom VirtualPathProvider
C_sharp : This is a followup to this question : Cast < int > .Cast < int ? > applied on generic enum collection results in invalid cast exceptionWhy is that Gender [ ] is IEnumerable < int > returns true in the generic case ? Especially when they are not type compatible ? It had tripped me in the question I linked ! I ...
enum [ ] is IEnumerable < int > returns true in a generic method
C_sharp : I think my logic is flawed ... .in a loop I have : this loop updates approximately once per second ... .the problem I have is that seconds always ends up with a zero ( 0 ) value . this is because the ItemPos value is always higher after first loop than elapsed.TotalSeconds . So for example : if 3 seconds pass...
Estimated time remaining , what am I missing ?
C_sharp : I was working through the MSDN tutorial for Crystal Reports , and I get to the Binding the Embedded Report to the CrystalReportViewer Control step : When I try the build , it tells me that I am missing my using declaration for Hierarchical_Grouping class . This brings up two questions for me ... What is the n...
Missing Using directive for hierarchical_grouping in MSDN crystal reports tutorial
C_sharp : Run enumeration of IAsyncEnumerable twice not possible ? Once CountAsync has been run , the await foreach wo n't enumerate any item . Why ? It seems there is no Reset method on the AsyncEnumerator.Source of data <code> var count = await itemsToImport.CountAsync ( ) ; await foreach ( var importEntity in itemsT...
Run enumeration of IAsyncEnumerable twice not possible ?
C_sharp : My answer to one of the question on SO was commented by Valentin Kuzub , who argues that inlining a property by JIT compiler will cause the reflection to stop working . The case is as follows : Fuzz function accepts a lambda expression and uses reflection to find the property . It is a common practice in MVC ...
Property / Method inlining and impact on Reflection
C_sharp : I have a 123MB big intarray , and it is basically used like this : eval ( ) is called a lot ( ~50B times ) with different c and I would like to know if ( and how ) I could speed it up . I already use a unsafe function with an fixed array that makes use of all the CPUs . It 's a C # port of the TwoPlusTwo 7 ca...
Speeding up array lookup after traversing ?
C_sharp : I 've found very strange C # compiler behavior for following code : In last line assert fails with following message : I understand why test fails : p2 = new SqlParameter ( `` @ p '' , 0 ) ; is resolved as SqlParameter ( string , SqlDbType ) and for other cases as SqlParameter ( string , object ) . But I do n...
Strange C # compiler behavior ( overload resolution )
C_sharp : I have a few jobs executed one after the other via ContinueJobWith < MyHandler > ( parentJobId , x = > x.DoWork ( ) ) .However , the second job is not getting processed and always sits in Awaiting state : The job itself is like this : Why this can happen and where to check for resultion ? We are using Autofac...
Hangfire ContinueWithJob is stuck in awaiting state , though parent job has succeeded
C_sharp : Is it possible somehow to define a constant that says what datatype to use for certain variables , similar to generics ? So in a certain class I would have something like the following : From the principle it should do the same as generics but I do n't want to write the datatype every time the constructor for...
C # : Declaring a constant variable for datatype to use
C_sharp : I made an winform application that can detect , set and toggle IPv4 settings using C # . When the user wants to get IP automatically from DHCP I call Automatic_IP ( ) : Automatic_IP : And in the Getip method I extract the current IP address , subnet , gateway and the DNS regardless of the fact that all these ...
Detecting if `` Obtain IP address automatically '' is selected in windows settings
C_sharp : I 'm developing a game using XNA and C # and was attempting to avoid calling new struct ( ) type code each frame as I thought it would freak the GC out . `` But wait , '' I said to myself , `` struct is a value type . The GC should n't get called then , right ? '' Well , that 's why I 'm asking here.I only ha...
What happens when value types are created ?
C_sharp : I saw the following code , Based on my understanding , I think the code should be rewritten as follows : Is that correct ? Based on http : //msdn.microsoft.com/en-us/library/scekt9xw % 28v=vs.80 % 29.aspxAn is expression evaluates to true if the provided expression is non-null , and the provided object can be...
C # -- Is this checking necessary `` obj is Person & & obj ! = null ''
C_sharp : I have two similar queries theoretically returning the same results : This request returns 0 items , even though it is supposed to return one.The following is a rewrite of the latter but with a call to the ToList ( ) method . This request works and returns the item expected in the first query ! Note : Session...
Unexpected Linq Behavior - ToList ( )
C_sharp : I am using HTML Agility pack in Xamarin forms to scrape data from a website . When a condition returns true , I want to send a push notification to all users . However , this data is changing a lot and I think it would cost a lot of internet data and maybe battery , if the device with this app is constantly c...
Use code on one device and show 'result ' with others using push notifications
C_sharp : Can I write a hash code function for the following comparer logic ? Two instances of My are equal if at least two properites from ( A , B , C ) match.The Equals part is simple , but I 'm stumped on the hash code part , and part of me is thinking it might not be possible.UPDATE : In addition to the correct ans...
Is it possible to write a hash code function for an comparer that matches many-to-many ?
C_sharp : The .NET reference source shows the implementation of NextBytes ( ) as : InternalSample provides a value in [ 0 , int.MaxValue ) , as evidenced by it 's doc comment and the fact that Next ( ) , which is documented to return this range , simply calls InternalSample . My concern is that , since InternalSample c...
Is Random.NextBytes biased ?
C_sharp : I 'm currently writing a CLR profiler , and I came across something very odd . When throwing two different exceptions , one from the try clause and one from the catch clause , the CLR notifies me of the same instruction pointer.More specifically : I 'm registered to receive the ExceptionThrown callbackvirtual...
CLR Profiling : DoStackSnapshot after a throw inside a catch block gives wrong instruction pointer
C_sharp : I 'm building a message dispatch map in C # and mostly just playing around with some different approaches . I am curious about a performance difference I am measuring , but it 's not obvious why from looking at the IL.The message map : I then have a class hierarchy of Messages , similar to EventArgs in WPF , ...
Why is casting to a generic type slower than an explicit cast in C # ?
C_sharp : I am trying to derive a class from ObservableCollection and I need to run just a single line of code each and every time any instance of this class is deserialized . My thought was to do this : But I do n't have access to those base methods related to serialization . Am I forced to re-write all of the seriali...
How can I run code in a C # class definition each time any instance of the class is deserialized ?
C_sharp : In MVC3 , we could use the CanvasAuthorize Attribute ( in old FaceBook version ) properties like LoginDisplayMode , ReturnUrlPath , CancelUrlPath.How can we use them in Latest version 6.4 ? We have [ FacebookAuthorize ( `` Permissions '' ) ] in the MVC4 . But , how we could use other properties like LoginDisp...
What is the substitute of CanvasAuthorizeAttribute in FaceBook C # SDK 6.4 version
C_sharp : Assume I have a classNow I want to filter duplicates in list of such audio 's by similarity ( not EXACT match ) condition . Basicaly it 's Levenstein distance with treshold correction by string total length . The problem is , general tip about IEqualityComparer is `` Always implement both GetHashCode and Comp...
.net Distinct ( ) and complex conditons
C_sharp : I want my View to be as follows : This leads me to believe I need a Model that contains a list of another Model . So in a project containing nothing but this I would have : Is this correct or is there a better way ? <code> @ model MyProgram.Models.DocumentList @ { ViewBag.Title = `` View1 '' ; } @ foreach ( M...
Simple best practices for ASP.NET models
C_sharp : I understand that .NET is multi-threaded and that is a good thing , but I continually run into issues when I have a background worker for example that is updating some control on my form and I have to do : My question is why is this not built into the framework - surely if I am trying to update a DataGridView...
Why is n't Invoke via Delegate built into .NET
C_sharp : I have a LinqToEntities query that double produces a subquery when creating the SQL . This causes the result set to come back with 0-3 results , every time the query is run . The subquery on its own produces a single random result ( as it should ) . What is going on here ? The LINQ query : Produce this SQL : ...
LinqToEntities produces incorrect SQL ( Doubled Subquery )
C_sharp : If I include outside reference inside where predicate then memory does not get releases.Let 's say I have a List < object > then if I write a where predicate like this : Even If I make myList = null or predicate = null , it is not releasing memory . I have List < object > itemsource binded to DataGrid . I als...
Where predicates does not releases memory
C_sharp : I built an application that can also be ran as a service ( using a -service ) switch . This works perfectly with no issues when I 'm running the service from a command prompt ( I have something set up that lets me debug it from a console when not being ran as a true service ) . However , when I try to run it ...
Using memory maps with a service
C_sharp : I have many working Entity Framework Scalar Function 's . However , when I try to return a 'truthy ' value through a scalar function I get the following exception : The specified method 'Boolean svfn_CanCloneDocument ( Int32 , System.String ) ' on the type 'ETC.Operations.DbClient.DbClient.Data.DbClientContex...
Bit-Bool on a Entity Framework Scalar Function Throws ' can not be translated ' Exception
C_sharp : Let 's have two code snippets : A : B : In case A the CLR will not even call the Bar ctor ( unless it is debug build or the debugger is attached ) , however in case B it is called under all circumstances.The thing is that in Bar constructor one can have calls that will make this instance reachable from elsewh...
Why CLR optimizing away unused static field with initialization ?
C_sharp : So I have been playing around with C # lately and I do n't understand output formatting.OutputMy expected output was index i holds number Number [ i ] . So can anyone explain what to change , or link me with a good C # page on output formatting topic.I know there is a way to do it in 2 lines . <code> using Sy...
Simple C # output
C_sharp : I 've been playing around with optional parameters and came accross the following scenario.If I have a method on my class where all the parameters are optional I can write the following code : If I then create an interface such as : If I make the Test class implement this interface then it wo n't compile as i...
When interface method has no parameters why is n't the implementation recognised of a method with all optional parameters ?
C_sharp : I am trying to implement a caching mechanism for enumerating collections safely , and I am checking if all modifications of the built-in collections are triggering an InvalidOperationException to be thrown by their respective enumerators . I noticed that in the .NET Core platform the Dictionary.Remove and Dic...
Dictionary methods Remove and Clear ( .NET Core ) modify the collection during enumeration . No exception thrown
C_sharp : I am writing a simple Memoize helper that allows caching method results instead of computing them every time . However , when I try to pass a method into Memoize , the compiler ca n't determine the type arguments . Are n't they obvious from my method signature ? Is there a way around this ? Sample code : Erro...
Why do I have to explicitly specify my type arguments for Func parameters ?
C_sharp : Running an empty for-loop with large numbers of iterations , I 'm getting wildly different numbers in how long it takes to run : The above will run in around 200ms on my machine , but if I increase it to 1000000001 , then it takes 4x as long ! Then if I make it 1000000002 , then it 's down to 200ms again ! Th...
for-loop performance oddity in .NET x64 : even-number-iteration affinity ?
C_sharp : I am trying to enumerate a large IEnumerable once , and observe the enumeration with various operators attached ( Count , Sum , Average etc ) . The obvious way is to transform it to an IObservable with the method ToObservable , and then subscribe an observer to it . I noticed that this is much slower than oth...
Why is IEnumerable.ToObservable so slow ?
C_sharp : I have : How I make it , as MyBook to inherit the top-level Book namespace , instead of Company 's ? <code> namespace Book { ... } ... ... namespace Company { public class Book { } ... ... ... ... ... ... public class MyBook : Book.smth { } }
When same-named namespaces exist ( in current scope ) , how to refer any of them ?
C_sharp : I have a working solution for WP8.0 . But I needed to upgrade to get access to WNS . I have succeeded in adding WNS to the upgrade solution in the main menu works . But after Upgrading to wp8.1 ( silverlight ) , I have had some weird errors , that only happens on runtime . As an example it happens in the foll...
xaml parse error on interaction triggers wp8.1 ( silverlight )
C_sharp : what 's the difference for the following two ways to define namespace ? in some where I may have Both need to do the same to use class AA by using A.B.C ; Can I use C.AA a ; to specify the AA class in C namespace or I have to use the fall namespace convention : A.B.C.AA a ; to avoid possbile confliction ? <co...
C # namespace questions
C_sharp : I 'm trying to create an extension VSPackage for VS2017 ( in C # ) which would convert binary data to XML , opens that in the default VS XML editor and XML language service , and then converts it back to binary upon saving.However , I have troubles to line out which steps would be required for this . I though...
VSX : How can I reuse the existing XML editor to handle binary files converted to XML ?
C_sharp : I have a byte array that looks something like this : My end goal is to split this array into sub array 's anytime I see the sequence { 0x13 , 0x10 } . So my desired result on the example array would be : Ideally , I would also need to know that the final array , { 0x75 , 0x3a , 0x13 } , did not end with the s...
How to properly search and parse an array using a sequence of elements as the target
C_sharp : I 'm in a situation where two calls at the same time write to the session ( of an asp.net core application running on the old framework ) , and one of the session variables gets overwritten.Given the following controller code , assume that the long session gets called first , 200 ms later the short session ge...
ASP.NET session is overwritten
C_sharp : I 'm slowly getting my head around delegates , in that the signature of the delegate must match that of the method it is delegating too.However , please review the following code . I am now stumped at this point , because the delegate returns void ( as that is what SaveToDatabase ( ) is ) but , it 's clearly ...
How does the keyword delegate work compared to creating a delegate
C_sharp : Hello I 'm try to remove special characters from user inputs . At the end I 'm turning it back to a string . My code only removes one special character in the string . Does anyone have any suggestions on a easier way instead <code> public void fd ( ) { string output = `` '' ; string input = Console.ReadLine (...
Special characters Regex
C_sharp : From https : //msdn.microsoft.com/en-us/library/d5x73970.aspx When applying the where T : class constraint , avoid the == and ! = operators on the type parameter because these operators will test for reference identity only , not for value equality . This is the case even if these operators are overloaded in ...
C # generic types equality operator
C_sharp : How would I get change this snippet to correctly add an instance of A to a List < A > , B to a List < B > , etc . ? The exception is thrown because , while the Add ( ) is found by the binder , it passes in dynamic which fails overload resolution . I prefer not to change the above to use reflection , or at lea...
How to add a T to List < T > where List < T > masquerades as 'dynamic ' and T as 'object ' ?
C_sharp : To my surprise I have discovered a powerful feature today . Since it looks too good to be true I want to make sure that it is not just working due to some weird coincidence.I have always thought that when my p/invoke ( to c/c++ library ) call expects a ( callback ) function pointer , I would have to pass a de...
Delegate on instance method passed by P/Invoke
C_sharp : Is there a way in C # to disable keyword 's functionality in code ? In my case I want to define one of my enum items as float which obviously makes Visual Studio a bit confused : ) <code> public enum ValidationType { email , number , float , range }
C # disable keyword functionality
C_sharp : What does = > means ? Here 's a code snap : <code> Dispatcher.BeginInvoke ( ( Action ) ( ( ) = > { trace.Add ( response ) ; } ) ) ;
What does '= > ' mean ?
C_sharp : I have the below method where I need to check for some certain strings which could be in any case and then remove them . Just wondered if there was a better performing way ? <code> private void MyMethod ( string Filter ) { //need to remove < Filter > and < /Filter > case in-sensitive var result = Filter.ToLow...
Out of curiosity - is there a better performing approach to do this string replace ?
C_sharp : Can anyone think of good Resharper pattern that will detect the following bug : I 've tried creating a pattern but I ca n't work out how to quickly handle all types of arithmetic ( e.g . + , - , * etc ) , and any nullable type ( e.g . Nullable < int > , Nullable < decimal > , Nullable < double > etc ) . Also ...
Resharper pattern to detect arithmetic with nullable types
C_sharp : This is homework ! ! ! Please do not interpret this as me asking for someone to code for me.My Program : http : //pastebin.com/SZP2dS8D This is my first OOP . The program works just fine without user input ( UI ) , but the implementation of it renders my design partially ineffective . I am not using a List co...
C # : Bad design of class ( first OOP )
C_sharp : In my BL ( will be a public API ) , I am using ICollection as the return types in my Find methods , like : Note the use of ICollection instead of Collection < > .Now in my GUI , I need to cast the results back to Collection , like : This is because I need to use some Collection < > specific methods on my retu...
Question regarding return types with collections
C_sharp : I have the following in my controller ; This only occurs 4 times but it bugs me that I have the code repeated 4 times.I then have a BaseController that then grabs the parameters and does stuff with them ; I 'd like to be able to do away with the Post ActionResult 's and have a single one in a base controller ...
Create common ActionResult
C_sharp : tl ; dr : Overriding a generic iterator method in a constructed derived class results in a BadImageFormatException being thrown when compiled with Visual Studio 2010 ( VS2010 ) , regardless of .NET version ( 2.0 , 3.0 , 3.5 or 4 ) , platform or configuration . The problem is not reproducible in Visual Studio ...
Overriding generic iterator results in BadImageFormatException when compiled with Visual Studio 2010
C_sharp : I 've considered 2 cases : Ideone : http : //ideone.com/F8QwHYand : Ideone : http : //ideone.com/hDTcxXThe question is why does order of fields actually matter ? Is there any reason for this or it 's just simply because it is ( such is the design ) .If the reason is just that anonymus types are not supposed t...
Why does compiler generate different classes for anonymous types if the order of fields is different
C_sharp : The following is a simplified version of the problem I 'm having : The comments are the values from the watch window in Visual Studio 2017However if I enter : in the watch window , I get : So how come I can cast it in the watch window and it works , but if I do it in the code it evaluates to null ? <code> var...
Casting object to IEnumerable < object >
C_sharp : i ca n't understand the difference between a simple bare and I know I can use it only if i have a +1 overloaded ctor , but I ca n't understand the advantages of defining the parameterless constructor this way . <code> Public ClassName ( ) { } Public ClassName ( ) : this ( null ) { }
When and why should I use ClassName : this ( null ) ?
C_sharp : Simplified , i have these 2 Extension method : And here is where i use them : I have more GetString ( ) extensions.My try { ... } catch { ... } is getting large and basically i search for ways to shorten it down to 1 catch that calls the extension based on the type of the exception.Is there a way to call the ...
Calling extension method 's overload with derived type
C_sharp : While removing some obsolete code I came across an unexpected scenario , recreated below : Based in the output it seems that functions deprecated with a warning are permitted to call functions deprecated with an error and the code will execute . My expectation was that I would see a compiler error complaining...
Deprecation behavior using the [ Obsolete ] attribute
C_sharp : EDIT : see my update below on my stance on Null in C # 8.0 before giving me options to patterns and suchOriginal questionI am trying to upgrade my base libraries to be `` null enabled '' , aka using the C # 8.0 < Nullable > enable < /Nullable > flag.When trying to work with abstractions , and in specific gene...
Generics and Nullable ( class vs struct )
C_sharp : When calling a method with a ref or out parameter , you have to specify the appropriate keyword when you call the method . I understand that from a style and code quality standpoint ( as explained here for example ) , but I 'm curious whether there is also a technical need for the keywords to be specified in ...
Is there a technical reason for requiring the `` out '' and `` ref '' keywords at the caller ?
C_sharp : Could someone point out why this could be happening : I am using NHibernate and the Linq provider for it.The code that fails is listed here : Debugging shows that sequence ( which is an IQueryable < T > ) after this contains 2 elements , which were added to the database.I expect the first Where statement to y...
C # strange lambda behavior
C_sharp : I am using Xamarin.Forms and I have 2 pages , one is a List View , the other is a just a view I am using as a filter for the List View . I am currently using Navigation.PushAsync to display this page , my question is , is there away to present it like a side menu ? I know there is Master Detail View which I a...
Xamarin.Forms Navigation.PushAsync as Side Menu
C_sharp : I am using the debugger to step through my code . The code file I ’ m in has usings at the top , including for exampleIn Visual Studio 2008 this used to apply to the Watch window while debugging , so I could use extension methods such as .First ( ) and .ToArray ( ) in the watch window.For some reason , this h...
Watch window stopped accepting some usings
C_sharp : The following code does n't compile ( error CS0123 : No overload for 'System.Convert.ToString ( object ) ' matches delegate 'System.Converter < T , string > ' ) : however , this does : In c # 4 , co/contra-variant delegates can be assigned to each other , and delegates can be created from co/contra-variant me...
How is method group overload resolution different to method call overload resolution ?
C_sharp : I have csv file with 30 000 lines . I have to select many values based on many conditions , so insted of many loops and `` if 's '' i decided to use linq . I have written class to read csv . It implements IEnumerable to be used with linq . This is my enumerator : It 's working , but it 's slow . Let 's say i ...
Is possible to change search method in LINQ ?
C_sharp : When im passing Bmp as stream , function always return , but file saving on disk correctly.When I load bpm from disk , function return correct MD5 . Also passing `` new Bitmap ( int x , int y ) ; '' with different value return same MD5.Why its happening ? Can somebody explain this strange behaviour ? <code> D...
Problem with counting MD5 from bitmap stream C #
C_sharp : I 've got the following situation : There are two related types . For this question , I 'll use the following simple types : So that one Person might have multiple Accounts ( i.e. , multiple Accounts would reference the same PersonId ) .In our database , there are tens of thousands of persons , and each have ...
Retrieving large amount of records under multiple limitations , without causing an out-of-memory exception
C_sharp : Suppose I have the following : In what situation ( s ) would there be an advantage to using MyClassB over MyClassA ? <code> public class MyElement { } [ Serializable ] [ StructLayout ( LayoutKind.Sequential ) ] struct ArrayElement { internal MyElement Element ; } public class MyClass { internal MyElement Comp...
When to use an array of a value type containing a reference types over an array of a reference type ?
C_sharp : Given the following C # code : The question is : what is causing the type of i to be correctly inferred as an int ? This is not at all obviuous , as array2D is a rectangular array . It does not implement IEnumerable < int > . It also implements a GetEnumerator ( ) method , which returns a System.Collections.I...
Why does foreach ( var i in array2D ) work on multidimensional arrays ?
C_sharp : is it possible to differ the variable I 'm assigning to depending on a condition ? The issue I came across is wanting to do this : Instead ofWhich results in the following error Error CS0131 The left-hand side of an assignment must be a variable , property or indexerSo I was wondering if there was a way to do...
Is there a way to use a ternary operator - or similar method - for picking the variable to assign to ?