<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>Document</title></head><body><div id="root"></div><script src="../lib/react.js"></script><script src="../lib/react-dom.js"></script><script src="../lib/babel.js"></script><script type="text/babel">let message = "Hello World"function btnClick(){message = "Hello React"rootRender() }const root = ReactDOM.createRoot(document.querySelector("#root"))function rootRender() {root.render((<div><h2>{message}</h2><button onClick={btnClick}>修改文本</button></div>))}rootRender() </script></body></html>