源代码 ：
点击运行
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Bootstrap 实例 - 下拉菜单</title> <link rel="stylesheet" href="https://cdn.staticfile.org/twitter-bootstrap/3.3.7/css/bootstrap.min.css"> <script src="https://cdn.staticfile.org/jquery/2.1.1/jquery.min.js"></script> <script src="https://cdn.staticfile.org/twitter-bootstrap/3.3.7/js/bootstrap.min.js"></script> </head> <body> <div class="container"> <h2>向上下拉菜单</h2> <p>.dropup 类用于指定一个向上的下拉菜单。</p> <p>.dropdown-menu 类用于创建下拉菜单。</p> <div class="dropup"> <button class="btn btn-default dropdown-toggle" type="button" id="menu1" data-toggle="dropdown">教程 <span class="caret"></span></button> <ul class="dropdown-menu" role="menu" aria-labelledby="menu1"> <li role="presentation"><a role="menuitem" tabindex="-1" href="#">HTML</a></li> <li role="presentation"><a role="menuitem" tabindex="-1" href="#">CSS</a></li> <li role="presentation"><a role="menuitem" tabindex="-1" href="#">JavaScript</a></li> <li role="presentation" class="divider"></li> <li role="presentation"><a role="menuitem" tabindex="-1" href="#">关于我们</a></li> </ul> </div> </div> </body> </html>
运行结果