task3Demo/demo1.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>react demo</title>
    <script src="https://cdn.bootcss.com/react/16.8.6/umd/react.production.min.js"></script>
    <script src="https://cdn.bootcss.com/react-dom/16.8.6/umd/react-dom.production.min.js"></script>
    <script src="https://cdn.bootcss.com/babel-standalone/7.0.0-beta.3/babel.min.js"></script>
</head>
<body>
    <div id="root"></div>
    <script type="text/babel">
    // 复习前面的知识
    function App(){//react 函数组件
        return(
            <h1>hi</h1>
        )
    }
    class App2 extends React.Component{//react class组件
        render(){
            return(
                <h2>hi 2</h2>
            )
        }
    }
    ReactDOM.render(<App2 />,document.getElementById('root'))
    </script>
</body>
</html>