等待一个可观察物体在角度上解析

您可以在模板中添加以下内容:

<ng-container *ngIf="$loaded | async; else loading"> 
  <ng-container *ngIf="$user | async; else login"> 
      // redirect to home page
  </ng-container>

  <ng-template #login>
    // display login form
  </ng-template>
</ng-container>

<ng-template #loading>
   // loading
</ng-template>

  $loaded = this.$user.pipe(
    mapTo(true),
    startWith(false)
  );