左边漂浮菜单js代码

以下是一个简单的左边漂浮菜单的 JavaScript 代码示例：

<!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>漂浮菜单</title>
  <style>
    #floatMenu {
      position: fixed;
      left: 0;
      top: 50%;
      transform: translateY(-50%);
      z-index: 1000;
    }

    #floatMenu ul {
      list-style: none;
      padding: 0;
      margin: 0;
    }

    #floatMenu ul li {
      padding: 10px;
      background-color: #f1f1f1;
      margin-bottom: 5px;
      border-radius: 0 5px 5px 0;
    }
  </style>
</head>

<body>
  <div id="floatMenu">
    <ul>
      <li>菜单项 1</li>
      <li>菜单项 2</li>
      <li>菜单项 3</li>
    </ul>
  </div>

  <script>
    window.onload = function () {
      const floatMenu = document.getElementById('floatMenu');
      let isClicked = false;

      floatMenu.addEventListener('click', function () {
        isClicked = !isClicked;
        if (isClicked) {
          floatMenu.style.width = '200px';
        } else {
          floatMenu.style.width = '50px';
        }
      });

      document.addEventListener('click', function (event) {
        if (!floatMenu.contains(event.target) && isClicked) {
          isClicked = false;
          floatMenu.style.width = '50px';
        }
      });
    }
  </script>
</body>

</html>

基础概念：