二、子组件通过@Output向父组件传参

// 泛型:任意类型
class Person<T>{
    emit(msg:T){
        console.log(msg);
    }
}
var p = new Person<string>();
p.emit("hello world")

2-1 子组件引入Output和EventEmitter

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

2-2 子组件中实例化EventEmitter

@Output() private outer = new EventEmitter<string>();

2-3 子组件中通过EventEmitter实例化的对象outer,广播数据

handleClick(){
    this.outer.emit("101001");
}

<button (click)="handleClick()">向父传参</button>

2-4 父组件中接收事件

<app-header  (outer)="getId($event)"></app-header>

export class AppComponent {
  getId(id:string){
    console.log(id);
  }
}