<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no">
<title>Bootstrap(导航栏与下拉列表)</title>
<link rel="stylesheet" href="css/bootstrap.css">
<script src="js/jquery-3.2.1.js"> </script>
<script src="js/bootstrap.js"></script>
</head>
<body>
<div class="container">
<div class=" btn-group">
<button type="button" class="btn btn-primary btn-group-lg">天使</button>
<button type="button" class="btn btn-primary">安娜</button>
<button type="button" class="btn btn-primary">黑影</button>
<button type="button" class="btn btn-primary">士兵76</button>
<button type="button" class="btn btn-primary">源氏</button>
<button type="button" class="btn btn-primary">半藏</button>
<button type="button" class="btn btn-primary">麦克雷</button>
</div>
<div class="input-group">
<span class="input-group-addon">@</span>
<input type="text" class="form-control" placeholder="用户名">
</div>
<!--作为额外元素的按钮式下拉菜单 -->
<div class="input-group">
<div class="input-group-btn">
<button type="button" class="btn btn-primary dropdown-toggle" data-toggle="dropdown">我喜欢的游戏<span class="caret"></span></button>
<ul class="dropdown-menu">
<li><a href="#">虚幻争霸</a></li>
<li><a href="#">守望先锋</a></li>
<li><a href="#">神之浩劫</a></li>
<li class="divider">枪火游侠</li>
<li><a href="#">英雄联盟</a></li>
</ul>
</div>
</div>
</div>
</body>
</html>
原文：http://www.cnblogs.com/YoogaChan/p/6892046.html