index.html

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-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>
</head>

<body>
<!--
    创建节点
 -->
<div id="demoReact">

</div>
<script type="text/babel">
    let arr=["吃饭","睡觉","打豆豆"]
    let myDom=arr.map((item,index)=>{
        return( <p key={index}>{item}</p>)
    });
   ReactDOM.render(myDom,document.getElementById('demoReact'))
</script>
</body>

</html>

运行结果