Context

app.js

import React from 'react';
import Son from './components/son';//引入子组件
// 创建一个 theme Context,
export const {Provider,Consumer} = React.createContext("默认名称");
export default class App extends React.Component {
    render() {
        let name ="我是需要共享的数据"
        return (
            //Provider共享容器 接收一个name属性
            <Provider value={name}>
                <div style={{border:'1px solid red',width:'30%',margin:'50px auto',textAlign:'center'}}>
                    <p>父组件定义的值:{name}</p>
                    <Son />
                </div>
            </Provider>
        );
    }
}

son.js

//son.js 子类
import React from 'react';
import { Consumer } from "../../App";//引入父组件的Consumer容器
import Grandson from "../grandson";//引入子组件
function Son(props) {
    return (
        //Consumer容器,可以拿到上文传递下来的name属性,并可以展示对应的值
        <Consumer>
            {( name ) =>
                <div style={{ border: '1px solid blue', width: '60%', margin: '20px auto', textAlign: 'center' }}>
                    <p>子组件。获取父组件的值:{name}</p>
                    {/* 孙组件内容 */}
                    <Grandson />
               </div>
            }
        </Consumer>
    );
}
export default Son;

grandson.js

//grandson.js 孙类
import React from 'react';
import { Consumer } from "../../App";//引入父组件的Consumer容器
function Grandson(props) {
    return (
         //Consumer容器,可以拿到上文传递下来的name属性,并可以展示对应的值
        <Consumer>
            {(name ) =>
                   <div style={{border:'1px solid green',width:'60%',margin:'50px auto',textAlign:'center'}}>
                   <p>孙组件。获取传递下来的值:{name}</p>
               </div>
            }
        </Consumer>
    );
}
export default Grandson;