多组件嵌套

• webpack-dev-server环境运行起来,这里主要是明白了React如何做嵌套

• src/js/components下创建header.js书写代码✍️

import React from 'react';
import ReactDOM from 'react-dom';
export default class CompomentHeader extends React.Component{
  render(){
    return(
      <header>
      <h1>这里是表头</h1>
      </header>
    )
  }
}

• src/js/components下创建footer.js书写代码✍️

import React from 'react';
export default class CompomentFooter extends React.Component{
  render(){
    return(
      <footer>
      <h1>这里是尾部</h1>
      </footer>
    );
  }
}