React 学习项目搭建以及第一个demo组件

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学习视频地址

https://www.imooc.com/learn/1045

1 使用create-react-app 快速构建React开发环境

  $ cnpm install -g create-react-app

$ create-react-app my-app

$ cd my-app/

$ npm start

 

第一个组件：

import  React from 'react' class Welcome extends React.Component{     render(){         return <h1>hello world</h1>     }; } export default Welcome;

 

2 使用组件

import React from 'react'; import ReactDOM from 'react-dom'; import './index.css'; // import App from './App'; import Welcome from './Welcome'; import * as serviceWorker from './serviceWorker'; ReactDOM.render(<Welcome/>, document.getElementById('root')); // If you want your app to work offline and load faster, you can change // unregister() to register() below. Note this comes with some pitfalls. // Learn more about service workers: https://bit.ly/CRA-PWA serviceWorker.unregister();