具有手动刷新能力的ActivatedRoute observable

Question

我目前正在开发一个需要手动“从服务器重新获取”功能的 Angular 组件。

下面列出的版本有效，但有什么方法可以简化它？看起来有点复杂。

private refreshSignalSubject = new Subject<any>();
refreshSignal$: Observable<any> = this.refreshSignalSubject.asObservable();

ngOnInit() {
  this.item$ = combineLatest(
    this.route.paramMap.pipe(
      map(params => params.get('id')),
    ),
    this.refreshSignal$.pipe(
      startWith(() => Math.random())
    )
  ).pipe(
    map((values) => {
      const [id, _] = values
      return id
    }),
    switchMap(id => this.apiService.get(`/items/${id}`)),
    share()
  )
}

reloadItem() { // this method is triggered from the view and from other methods in this component
  this.refreshSignalSubject.next(Math.random());
}

Answer 1

你甚至不需要把它放在ngOnInit：

readonly items$ = combineLatest([
  this.route.params.pipe(
    map(({ id }) => id),
    distinctUntilChanged()
  ),
  this.refreshSignal$
]).pipe(
  switchMap(([ id ]) => this.apiService.get(`/items/${id}`)),
  shareReplay(1)
)

应该够了