原文出处：https://blog.csdn.net/inforstack/article/details/84305087?utm_medium=distribute.pc_relevant.none-task-blog-baidujs-1 啥也不说，贴出代码，看执行顺序。
import { Component } from '@angular/core'; import { HttpClient } from "@angular/common/http"; @Component({ selector: 'app-root', templateUrl: './app.component.html', styleUrls: ['./app.component.scss'] }) export class AppComponent { title = 'app'; constructor(private client:HttpClient){ this.initData().then(data => { console.log(data); console.log('constructor 执行完成') }); } async initData(){ let data = await this.getData(); console.log(data); console.log('initData 执行完成'); return data; } getData(){ let url = 'https://tieba.baidu.com/hottopic/browse/topicList'; let data = this.client.get(url).toPromise(); console.log(data); console.log('getData 执行完成'); return data; } }