Lab8(EventsWithEs6) copy.html

<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <title>React tutorial</title>
<script src="https://unpkg.com/react@17/umd/react.development.js" crossorigin></script>
<script src="https://unpkg.com/react-dom@17/umd/react-dom.development.js" crossorigin></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/babel-core/5.8.2/browser.min.js"></script>
  </head>
  <body>
    <div id="app"></div>
    <script type="text/babel">
    
   class FirstComponent extends React.Component {
    constructor() {
          super();
        this.state = {
              count: 0,
              };
          }
        updateCount() {
         this.setState((prevState, props) => {
             return { 
              count: prevState.count + 1 
              }
          });
          }
    componentDidUpdate() {
      console.log("ES6 update");
    }
  componentDidUpdate(prevProps, prevState) {
    if (prevState.count !== this.state.count) {
      console.log('count state has changed.')
    }
  }
    componentDidMount() {
      console.log("Mount by ES6");
    }
    render() {
      return (
      <div>
        <button onClick={() => this.updateCount()}>
        Clicked {this.state.count} times
        </button><br/>
        <h1>Hello World</h1>
      </div>
      )
    }
  }
   ReactDOM.render(
      <FirstComponent name="Shiv"/>,
      document.getElementById('app')
    );

    </script>
  </body>
</html>