Home.js

import React, {Component,Fragment} from 'react';
import ImgA from "../assset/index.jpg"
class Home extends Component {
    render() {
        return (
            <Fragment>
                <div>
                    你好我是组件{parseInt(Math.random()*10)}
                </div>
                <div>
                    你好我是组件2{parseInt(Math.random()*10)}
                    <img src={ImgA} alt=""/>
                </div>
            </Fragment>

        );
    }
}

export default Home;

 app.js

import React from 'react';
import logo from './logo.svg';
import './App.css';
import  Home from './components/Home.js'
function App() {
  return (
    <div className="App">
    <Home></Home>
    </div>
  );
}

export default App;