查询选项
在多个地方共享 queryKey 和 queryFn，同时保持它们彼此靠近的最佳方法之一是使用 queryOptions 助手。在运行时，此助手只返回您传递给它的任何内容，但在 TypeScript 中使用它 时，它有很多优点。您可以在一个地方定义查询的所有可能选项，并且您还将获得所有这些选项的类型推断和类型安全。
ts
import { queryOptions } from '@tanstack/angular-query-experimental'
@Injectable({
providedIn: 'root',
})
export class QueriesService {
private http = inject(HttpClient)
post(postId: number) {
return queryOptions({
queryKey: ['post', postId],
queryFn: () => {
return lastValueFrom(
this.http.get<Post>(
`https://jsonplaceholder.typicode.com/posts/${postId}`,
),
)
},
})
}
}
// usage:
postId = input.required({
transform: numberAttribute,
})
queries = inject(QueriesService)
postQuery = injectQuery(() => this.queries.post(this.postId()))
queryClient.prefetchQuery(this.queries.post(23))
queryClient.setQueryData(this.queries.post(42).queryKey, newPost)
import { queryOptions } from '@tanstack/angular-query-experimental'
@Injectable({
providedIn: 'root',
})
export class QueriesService {
private http = inject(HttpClient)
post(postId: number) {
return queryOptions({
queryKey: ['post', postId],
queryFn: () => {
return lastValueFrom(
this.http.get<Post>(
`https://jsonplaceholder.typicode.com/posts/${postId}`,
),
)
},
})
}
}
// usage:
postId = input.required({
transform: numberAttribute,
})
queries = inject(QueriesService)
postQuery = injectQuery(() => this.queries.post(this.postId()))
queryClient.prefetchQuery(this.queries.post(23))
queryClient.setQueryData(this.queries.post(42).queryKey, newPost)
对于无限查询，可以使用单独的 infiniteQueryOptions 助手。
您仍然可以在组件级别覆盖某些选项。一个非常常见且有用的模式是创建每个组件的 select 函数
ts
// Type inference still works, so query.data will be the return type of select instead of queryFn
queries = inject(QueriesService)
query = injectQuery(() => ({
...groupOptions(1),
select: (data) => data.title,
}))
// Type inference still works, so query.data will be the return type of select instead of queryFn
queries = inject(QueriesService)
query = injectQuery(() => ({
...groupOptions(1),
select: (data) => data.title,
}))
