Angular等待服务中组件的输出

import { Injectable } from '@angular/core';
import { Observable, of } from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class DataService {
  private data: string = 'Hello, World!';

  getData(): Observable<string> {
    return of(this.data);
  }
}

import { Component, OnInit } from '@angular/core';
import { DataService } from './data.service';

@Component({
  selector: 'app-my-component',
  template: `
    <div>{{ data }}</div>
  `
})
export class MyComponent implements OnInit {
  data: string;

  constructor(private dataService: DataService) { }

  ngOnInit() {
    this.dataService.getData().subscribe((result) => {
      this.data = result;
    });
  }
}