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>下拉菜单</h2> <p>在 .dropdown-menu 中添加 .dropdown-menu-right 类来设置下拉菜单右对齐：</p> <div class="dropdown"> <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 dropdown-menu-right" 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