<!DOCTYPE html>

<html>

<head>

<meta charset="utf-8">

<title>Bootstrap 分割的按钮下拉菜单</title>

<link rel="stylesheet" href="http://cdn.static.runoob.com/libs/bootstrap/3.3.7/css/bootstrap.min.css">  

</head>

<body>

<div class="container">

<div class="btn-group">

<button class="btn btn-default">默认</button>

<button class="btn btn-default dropdown-toggle" data-toggle="dropdown">

<span class="caret"></span>

<span class="sr-only">切换下拉菜单</span>

</button>

<ul class="dropdown-menu" role="menu">

       <li><a href="#">功能 1</a></li>

       <li><a href="#">功能 2</a></li>

       <li><a href="#">功能 3</a></li>

       <li class="divider"></li>

       <li><a href="#">功能 4</a></li>

   </ul>

</div>

<div class="btn-group">

<button class="btn btn-primary">默认</button>

<button class="btn btn-primary dropdown-toggle" data-toggle="dropdown">

<span class="caret"></span>

<span class="sr-only">切换下拉菜单</span>

</button>

<ul class="dropdown-menu" role="menu">

       <li><a href="#">功能 1</a></li>

       <li><a href="#">功能 2</a></li>

       <li><a href="#">功能 3</a></li>

       <li class="divider"></li>

       <li><a href="#">功能 4</a></li>

   </ul>

</div>

</div>

    <script src="http://cdn.static.runoob.com/libs/jquery/2.1.1/jquery.min.js"></script>

  <script src="http://cdn.static.runoob.com/libs/bootstrap/3.3.7/js/bootstrap.min.js"></script>

</body>

</html>