1.运行效果如图所示
2.实现代码如下
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <title>导航加下拉菜单（二级导航）</title> <!-- 最新版本的 Bootstrap 核心 CSS 文件 --> <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous"> <!-- 可选的 Bootstrap 主题文件（一般不用引入） --> <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap-theme.min.css" integrity="sha384-rHyoN1iRsVXV4nD0JutlnGaslCJuC7uwjduW9SVrLvRYooPp2bWYgmgJQIXwl/Sp" crossorigin="anonymous"> </head> <body> <ul class="nav nav-pills"> <li class="active"><a href="##">首页</a></li> <li class="dropdown"> <a href="##" class="dropdown-toggle" data-toggle="dropdown"> 教程<span class="caret"></span></a> <ul class="dropdown-menu"> <li><a href="##">CSS3</a></li> <li><a href="##">Sass</a></li> <li><a href="##">jQuery</a></li> <li><a href="##">Responsive</a></li> </ul> </li> <li><a href="##">关于我们</a></li> </ul> <script src="https://cdn.bootcss.com/jquery/3.2.1/jquery.min.js"></script> <!-- 最新的 Bootstrap 核心 JavaScript 文件 --> <script src="https://cdn.bootcss.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script> </body> </html>
本文转自 素颜猪 51CTO博客，原文链接:http://blog.51cto.com/suyanzhu/1929074
