快速起步一个简单ReactApp

index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1" />
    <title>My Simple React App</title>
    <link rel="icon" href="favicon.svg" />

    <!-- app styles -->
    <style>
      body {
        margin: 0;
        padding: 0;
      }
    </style>
  </head>
  <body>
    <div class="app"></div>

    <!-- app logics -->
    <script src="https://unpkg.com/react@18/umd/react.development.js"></script>
    <script src="https://unpkg.com/react-dom@18/umd/react-dom.development.js"></script>
    <script src="https://unpkg.com/@babel/standalone/babel.min.js"></script>
    <script type="text/babel">
      (function (window) {
        'use strict';

        function App() {
          const [count, setCount] = React.useState(0);

          return (
            <div>
              <button onClick={() => setCount(count - 1)}>-</button>
              <span>{count}</span>
              <button onClick={() => setCount(count + 1)}>+</button>
            </div>
          );
        }

        const root = ReactDOM.createRoot(document.querySelector('.app'));
        root.render(<App />);
      })(window);
    </script>
  </body>
</html>