js简单网页源码

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>简单网页</title>
</head>

<body>
  <h1 id="title">欢迎来到我的网页</h1>
  <button id="btn">点击我</button>

  <script>
    // 获取元素
    var title = document.getElementById('title');
    var btn = document.getElementById('btn');

    // 点击按钮改变标题内容
    btn.onclick = function() {
      title.innerHTML = '你已经点击了按钮';
    }
  </script>
</body>

</html>