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---
id: infinite-queries
title: Infinite Queries
ref: docs/framework/react/guides/infinite-queries.md
replace:
{ 'useQuery': 'injectQuery', 'useInfiniteQuery': 'injectInfiniteQuery' }
---
[//]: # 'Example'
```angular-ts
import { Component, computed, inject } from '@angular/core'
import { injectInfiniteQuery } from '@tanstack/angular-query-experimental'
import { lastValueFrom } from 'rxjs'
import { ProjectsService } from './projects-service'
@Component({
selector: 'example',
templateUrl: './example.component.html',
})
export class Example {
projectsService = inject(ProjectsService)
query = injectInfiniteQuery(() => ({
queryKey: ['projects'],
queryFn: async ({ pageParam }) => {
return lastValueFrom(this.projectsService.getProjects(pageParam))
},
initialPageParam: 0,
getPreviousPageParam: (firstPage) => firstPage.previousId ?? undefined,
getNextPageParam: (lastPage) => lastPage.nextId ?? undefined,
maxPages: 3,
}))
nextButtonDisabled = computed(
() => !this.#hasNextPage() || this.#isFetchingNextPage(),
)
nextButtonText = computed(() =>
this.#isFetchingNextPage()
? 'Loading more...'
: this.#hasNextPage()
? 'Load newer'
: 'Nothing more to load',
)
#hasNextPage = this.query.hasNextPage
#isFetchingNextPage = this.query.isFetchingNextPage
}
```
```angular-html
<div>
@if (query.isPending()) {
<p>Loading...</p>
} @else if (query.isError()) {
<span>Error: {{ query?.error().message }}</span>
} @else { @for (page of query?.data().pages; track $index) { @for (project of
page.data; track project.id) {
<p>{{ project.name }} {{ project.id }}</p>
} }
<div>
<button (click)="query.fetchNextPage()" [disabled]="nextButtonDisabled()">
{{ nextButtonText() }}
</button>
</div>
}
</div>
```
[//]: # 'Example'
[//]: # 'Example1'
```angular-ts
@Component({
template: ` <list-component (endReached)="fetchNextPage()" /> `,
})
export class Example {
query = injectInfiniteQuery(() => ({
queryKey: ['projects'],
queryFn: async ({ pageParam }) => {
return lastValueFrom(this.projectsService.getProjects(pageParam))
},
}))
fetchNextPage() {
// Do nothing if already fetching
if (this.query.isFetching()) return
this.query.fetchNextPage()
}
}
```
[//]: # 'Example1'
[//]: # 'Example3'
```ts
query = injectInfiniteQuery(() => ({
queryKey: ['projects'],
queryFn: fetchProjects,
getNextPageParam: (lastPage, pages) => lastPage.nextCursor,
getPreviousPageParam: (firstPage, pages) => firstPage.prevCursor,
}))
```
[//]: # 'Example3'
[//]: # 'Example4'
```ts
query = injectInfiniteQuery(() => ({
queryKey: ['projects'],
queryFn: fetchProjects,
select: (data) => ({
pages: [...data.pages].reverse(),
pageParams: [...data.pageParams].reverse(),
}),
}))
```
[//]: # 'Example4'
[//]: # 'Example8'
```ts
injectInfiniteQuery(() => ({
queryKey: ['projects'],
queryFn: fetchProjects,
initialPageParam: 0,
getNextPageParam: (lastPage, pages) => lastPage.nextCursor,
getPreviousPageParam: (firstPage, pages) => firstPage.prevCursor,
maxPages: 3,
}))
```
[//]: # 'Example8'
[//]: # 'Example9'
```ts
injectInfiniteQuery(() => ({
queryKey: ['projects'],
queryFn: fetchProjects,
initialPageParam: 0,
getNextPageParam: (lastPage, allPages, lastPageParam) => {
if (lastPage.length === 0) {
return undefined
}
return lastPageParam + 1
},
getPreviousPageParam: (firstPage, allPages, firstPageParam) => {
if (firstPageParam <= 1) {
return undefined
}
return firstPageParam - 1
},
}))
```
[//]: # 'Example9'
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