Angular 2在发出事件时调用函数/方法

<button (click)="myFunction()">Click me</button>

import { Component, EventEmitter, Output } from '@angular/core';

@Component({
  selector: 'app-child',
  template: `
    <button (click)="onClick()">Click me</button>
  `
})
export class ChildComponent {
  @Output() customEvent = new EventEmitter();

  onClick() {
    this.customEvent.emit('Custom event emitted');
  }
}

@Component({
  selector: 'app-parent',
  template: `
    <app-child (customEvent)="onCustomEvent($event)"></app-child>
  `
})
export class ParentComponent {
  onCustomEvent(event: string) {
    console.log(event);
  }
}