代码：
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <!DOCTYPE html> <html> <head> <title>First DApp Demo</title> <link rel="stylesheet" type="text/css" href="main.css"> <script src="https://cdn.jsdelivr.net/npm/web3@latest/dist/web3.min.js"></script> <!-- 引入web3 --> </head> <body> <div class="container"> <h1>First DApp Demo</h1> <h2 id="info"> </h2> <label>姓名：</label> <input id="name" type="text" name=""> <label>年龄：</label> <input id="age" type="text" name=""> <button id="button">更新内容</button> </div> <script> console.log("web3:" + web3); </script> </body> </html>
报错： Uncaught ReferenceError: web3 is not defined at index.html:23
