Angular 4从数组到模板设置一个随机字符串值，并在两秒后更改为另一个字符串

// app.component.ts
import { Component } from '@angular/core';
import { timer } from 'rxjs';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
  randomString: string;

  constructor() {
    this.randomString = this.getRandomString();
    this.changeStringAfterDelay();
  }

  getRandomString() {
    const characters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
    let result = '';
    for (let i = 0; i < 10; i++) {
      result += characters.charAt(Math.floor(Math.random() * characters.length));
    }
    return result;
  }

  changeStringAfterDelay() {
    timer(2000).subscribe(() => {
      this.randomString = this.getRandomString();
    });
  }
}

<!-- app.component.html -->
<div>{{ randomString }}</div>