站长资讯网
最全最丰富的资讯网站

了解一下angular中的@Input()和@Output()

了解一下angular中的@Input()和@Output()

相关教程推荐:angularjs(视频教程)

创建 Student class

就只有几个简单的属性(执行下面的属性可以快速生成)
ng generate class entity/student

export class Student {     id: number;     name: string;     age: number; }

创建child component

ts

import { Component, OnInit, Input, Output, EventEmitter } from '@angular/core'; import { Student } from '../entity/student'; @Component({   selector: 'app-child',   templateUrl: './child.component.html',   styleUrls: ['./child.component.css'] }) export class ChildComponent implements OnInit {   @Input() stu: Student;   @Output() deleteEvent = new EventEmitter<number>();   constructor() { }   ngOnInit() {   }   delete(id) {     this.stu = null;     this.deleteEvent.emit(id);   } }

html

<p *ngIf="stu">   {{stu.id}} -- {{stu.name}} -- {{stu.age}}  <button (click)="delete(stu.id)">delete</button> </p>

修改 app.component

ts

import { Component } from '@angular/core'; import { Student } from './entity/student'; @Component({   selector: 'app-root',   templateUrl: './app.component.html',   styleUrls: ['./app.component.css'] }) export class AppComponent {   stus: Student[] = [     {id: 1, name: '里斯', age: 3},     {id: 2, name: '里斯2', age: 4},     {id: 3, name: '里斯3', age: 5},   ];   stu: Student;   constructor() {   }   selected(stu) {     this.stu = stu;   }   deleteStu(id: number) {     this.stus.forEach((val, index) => {       if ( val.id === id) {         this.stus.splice(index, 1);         return;       }     });   } }

html

<p>   <ul>     <li *ngFor="let stu of stus" (click)="selected(stu)"> {{stu.id}} -- {{stu.name}} -- {{stu.age}} </li>   </ul> </p> <app-child [stu]="stu" (deleteEvent)="deleteStu($event)"></app-child>

@Input() 很简单,就是将父组件的数据给子组件的一个属性;
@Output() 子组件创建一个 EventEmitter, 子组件的操作会触发EventEmitter ,然后将这个 EventEmitter 对象赋值给 父组件的一个 method ,改方法会拿到EventEmitter对象给的参数,然后进行处理;

赞(0)
分享到: 更多 (0)
网站地图   沪ICP备18035694号-2    沪公网安备31011702889846号