一、准备工作

1.定义一个父组件，名字为Parent

/src/component/Parent.js

import React, {Component} from 'react' export default class Parent extends Component { constructor(props) { super(props) this.state = { name: '我是父组件', msg: '父组件传值给子组件' } } render() { return ( <div> <h2>{ this.state.name }</h2> </div> ) } }

2.定义一个子组件 ，名字为Children

/src/component/Children.js

import React, {Component} from 'react' export default class Children extends Component { constructor(props) { super(props) this.state = { name: '我是子组件', msg: '子组件传值给父组件' } } render() { return ( <div> <h2>{ this.state.name }</h2> </div> ) } }

3.先在App.js里引入父组件Parent

/src/App.js

import React from 'react'; import Parent from './component/Parent' function App() { return ( <div> <Parent/> </div> ); } export default App;

运行项目：

 

编译成功

界面如图所示，http://localhost:3000/

4.父组件Parent引入子组件Children

import React, {Component} from 'react' import Children from './Children' export default class Parent extends Component { constructor(props) { super(props) this.state = { name: '我是父组件', msg: '父组件传值给子组件' } } render() { return ( <div> <h2>{ this.state.name }</h2> <h3>我要引入子组件了：</h3> <hr/> <Children/> </div> ) } }

已成功引入子组件

二、子组件Children传值(msg)给父组件Parent

子组件传值给父组件的步骤：

父组件在调用子组件时，传入一整个组件给子组件<Children parent={ this } />父组件中定义一个方法getChildrenMsg(resulet, msg)，用来获取子组件传来的值以及执行其他操作子组件在通过this.props来获取到一整个组件this.props.parent或者this.props[parent]子组件调用父组件步骤2里定义的方法，通过bind绑定传值

Parent:

import React, {Component} from 'react' import Children from './Children' export default class Parent extends Component { constructor(props) { super(props) this.state = { name: '我是父组件', msg: '父组件传值给子组件', childrenMsg: '' } } getChildrenMsg = (result, msg) => { // console.log(result, msg) // 很奇怪这里的result就是子组件那bind的第一个参数this，msg是第二个参数 this.setState({ childrenMsg: msg }) } render() { return ( <div> <h2>{ this.state.name }</h2> <h3>子组件传来的值为：{ this.state.childrenMsg }</h3> <h3>我要引入子组件了：</h3> <hr/> <Children parent={ this } /> </div> ) } }

Children:

import React, {Component} from 'react' export default class Children extends Component { constructor(props) { super(props) this.state = { name: '我是子组件', msg: '子组件传值给父组件' } } toParent = () => { // console.log(this.props.parent.getChildrenMsg.bind(this, this.state.msg)) this.props.parent.getChildrenMsg(this, this.state.msg) } render() { return ( <div> <h2>{ this.state.name }</h2> <button onClick={ this.toParent }>子组件传入给父组件</button> </div> ) } }

三、子组件Children给父组件Parent传一整个组件（父组件获取整个子组件）

子组件给父组件传一整个组件（父组件获取整个子组件）的步骤：

父组件在调用子组件时，通过ref属性，拿到整个子组件<Children ref='children'>父组件中通过this.refs.children或者this.refs[children]获取到一整个子组件实例（注意，要在DOM加载后才能获取）

Parent:

import React, {Component} from 'react' import Children from './Children' export default class Parent extends Component { constructor(props) { super(props) this.state = { name: '我是父组件', msg: '父组件传值给子组件', childrenMsg: '' } } getChildrenMsg = () => { this.setState({ childrenMsg: this.refs['children'].state.msg }) } render() { return ( <div> <h2>{ this.state.name }</h2> <button onClick={ this.getChildrenMsg }>获取更新子组件的msg值</button> <h3>子组件传来的值为：{ this.state.childrenMsg }</h3> <h3>我要引入子组件了：</h3> <hr/> <Children ref="children" /> </div> ) } }

Children:

import React, {Component} from 'react' export default class Children extends Component { constructor(props) { super(props) this.state = { name: '我是子组件', msg: '子组件传值给父组件' } } render() { return ( <div> <h2>{ this.state.name }</h2> <h3>子组件的msg为：{ this.state.msg }</h3> </div> ) } }

初始页面，点击按钮

 

点击按钮后

四、子组件Children给父组件Parent传方法

在第三点获取到整个组件的前提上，再获取方法，所以不详细讲了。