为类添加局部状态.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>状态state</title>
  <script src="./js/react.js"></script>
  <script src="./js/react-dom.js"></script>
  <script src="./js/browser.js"></script>
  <script type="text/babel">
    class Comp extends React.Component {
      constructor(props) {
        super(props);
        this.state = {date: new Date()};
      }
      render(){
        return(
          <div>
            <h1>hello, world!</h1>
            <h2>It is {this.state.date.toLocaleString()}</h2>
          </div>
        );
      }
    }
    ReactDOM.render(
      <Comp />,
      document.getElementById('div1')
    )
  </script>
</head>
<body>
  <div id="div1"></div>
</body>
</html>