Angular RxJS：合并 2 个 observables 的结果

Question

I have 2 Observable and I wish to see if both end up being "true". The http get observal never fires though?

    const storeAuth = this.store.isLoggedIn$;
    const heartBeatAuth = this.http.get<boolean>('/api/auth/heartbeat');

    return merge(storeAuth, heartBeatAuth).pipe(
      map((a, b) => {
        if (a && b) {
          return true;
        }
        this.router.navigateByUrl('/login');
        return false;
      }),
      take(1)
    );

Answer 1

merge does not emit an a and b like that, use combineLatest if you want both results at the same time. Merge will emit the first result from either stream then the next.

return combineLatest([storeAuth, heartBeatAuth]).pipe(
      map(([a, b]) => {

combineLatest emits an array so you can destructure a and b out of the array with [a, b]

No http requests will be fired until something subscribes to the returned observable.