<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script src="./node_modules/react/umd/react.development.js"></script>
    <script src="./node_modules/react-dom/umd/react-dom.development.js"></script>
    <script src="./node_modules/babel-standalone/babel.min.js"></script>
    <script src="./node_modules/prop-types/prop-types.js"></script>
</head>
<body>
<div id="demoReact">

</div>
<script type="text/babel">
class Com extends  React.Component{
    constructor(props) {
        super(props);
        this.state={
            name:"画画"
        }
    }
    render(){
        return(
            <div>
            <button onClick={()=>{this.setState({name:"hhah"})}}>点我</button>
            <div>我是一个组件---{this.state.name}</div>
            </div>
        )
    }
}

        ReactDOM.render(<Com />,document.getElementById('demoReact'))



</script>
</body>
</html>

运行结果