首页 | 简单教程,简单编程

代码编辑器：

<!DOCTYPE htm>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
<script src="https://cdn.bootcss.com/jquery/1.12.4/jquery.js"></script>
<script src="https://cdn.bootcss.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<nav class="navbar navbar-default" role="navigation">
    <div class="container-fluid"> 
        <div class="navbar-header">
            <a class="navbar-brand" href="#">简单教程</a>
        </div>
        <div id="myexample">
            <ul class="nav navbar-nav">
                <li class="active"><a href="#">HTML 5</a></li>
                <li><a href="#">CSS 3</a></li>
                <li class="dropdown">
                    <a href="#" class="dropdown-toggle" data-toggle="dropdown">
                        后端 
                        <b class="caret"></b>
                    </a>
                    <ul class="dropdown-menu">
                        <li><a href="#">Python</a></li>
                        <li><a href="#">PHP</a></li>
                        <li><a href="#">JAVA</a></li>
                        <li class="divider"></li>
                        <li><a href="#">分离的链接</a></li>
                        <li class="divider"></li>
                        <li><a href="#">另一个分离的链接</a></li>
                    </ul>
                </li>
                <li><a href="#">JavaScript</a></li>
            </ul>
        </div>
    </div>
</nav>
<script>
$(function() { $(".dropdown-toggle").dropdown('toggle');});
</script>

代码编辑器：

运行结果：