如何等待功能完成

Question

我希望仅在功能this.refresh()完成后才能启动功能this.getAuthorizedDatabases()。 您对如何轻松做到这一点有任何想法吗？

谢谢。

  ngOnInit() {
      this.userService.currentUser
      .subscribe(res => {
        this.user = res;
        this.getAuthorizedDatabases();

      });
     this.refresh();
  }

Answer 1

除非getAuthorizedDatabases()也可以异步进行

   ngOnInit() {
          this.userService.currentUser
          .subscribe(res => {
            this.user = res;
            this.getAuthorizedDatabases();
            this.refresh();
          });

Observable是异步的，执行不会等待Observable完成。

Answer 2

如果getAuthorizedDatabases()是同步的。

 ngOnInit() {
    this.userService.currentUser
        .subscribe(res => {
            this.user = res;
            this.getAuthorizedDatabases();
            this.refresh();
        });
}

如果getAuthorizedDatabases()是异步的。使用Async-await

 async ngOnInit() {
    this.userService.currentUser
        .subscribe(res => {
            this.user = res;
            await this.getAuthorizedDatabases();
            this.refresh();
        });
}