bootstrap常用组件之头部导航实现代码

<nav class="navbar navbar-default navbar-inverse navbar-fixed-top"> //navbar-inverse 设置背景                                                        //navbar-fixed-top 设置头部固定在顶部,因此需要给body设置顶部padding,一般设置为padding-top:60px <div class="Container-fluid"> //container-fluid设置导航条内容是否有一定的内间距,如果class="container-fluid"则没有内间距,内容紧贴左侧        //如果设置class="container",则内容有一定的内间距,内容对称居中  <!-- Brand and toggle get grouped for better mobile display -->  <div class="navbar-header">   <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1" aria-expanded="false">    <span class="sr-only">Toggle navigation</span>    <span class="icon-bar"></span>    <span class="icon-bar"></span>    <span class="icon-bar"></span>   </button>   //这里是响应式的写法,在小屏幕上回显示三杆,无需改动   <a class="navbar-brand" href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >某管理系统</a>  </div>  <!-- Collect the nav links, forms, and other content for toggling -->  <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">   <ul class="nav navbar-nav">    <li class="active"><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >首页 <span class="sr-only">(current)</span></a></li>    <li class="dropdown">     <a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">功能 <span class="caret"></span></a>     <ul class="dropdown-menu">      <li class="dropdown-header" >业务功能</li>      <li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >信息建立</a></li>      <li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >信息查询</a></li>      <li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >信息管理</a></li>      <li role="separator" class="divider"></li>      <li class="dropdown-header" >系统功能</li>      <li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >设置</a></li>      <li role="separator" class="divider"></li>     </ul>    </li>    <li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >帮助</a></li>   </ul>   <form class="navbar-form navbar-left pull-right">    <div class="form-group">     <input type="text" class="form-control" placeholder="username...">     <input type="password" class="form-control" placeholder="password...">    </div>    <button type="submit" class="btn btn-default">Login</button>   </form>  </div><!-- /.navbar-collapse --> </div><!-- /.container-fluid --></nav>