代码示例:(标识:bs_form_select_disabled)
<!DOCTYPE html>
<html lang="en">
<head>
  <title>Bootstrap Example</title>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link href="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/5.1.2/css/bootstrap.min.css" rel="stylesheet">
  <script src="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/5.1.2/js/bootstrap.bundle.js"></script>
</head>
<body>

<div class="p-4">
  <h2>禁用选择菜单</h2>
  <p>请使用 disabled 属性禁用选择菜单:</p>
  <form>
   <select class="form-select" disabled>
     <option>1</option>
     <option>2</option>
     <option>3</option>
     <option>4</option>
   </select>
  </form>    
</div>

</body>
</html>
运行结果: