触发对角度2中的子组件的更改,即使数据/状态没有更改

你可以通过 Subject

在父组件中,创建一个主题,如下所示:

import { Component } from '@angular/core';
import { Subject } from 'rxjs';

@Component({
  selector: 'my-app',
  templateUrl: './app.component.html',
  styleUrls: [ './app.component.css' ]
})
export class AppComponent  {
  subject = new Subject<string>();

  handleClick() {
    // This will send a message via the subject
    this.subject.next("TEST");
  }

  // Complete the subject when your component is destroyed to avoid memory leaks
  ngOnDestroy() {
    this.subject.complete();
  }
}

<hello [notifier]="subject"></hello>

主题

import { Component, Input } from '@angular/core';
import { Subject } from 'rxjs';

@Component({
  selector: 'hello',
  template: `<h1>Hello {{name}}!</h1>`,
  styles: [`h1 { font-family: Lato; }`]
})
export class HelloComponent  {
  @Input() notifier: Subject<any>;

  ngOnInit() {
    if (this.notifier != null) {
      this.notifier.subscribe((event) => {
        // This will be logged every time the subject.next is called.
        console.log("HelloComponent heard", event);
      })
    }
  }
}

这是一个 StackBlitz example