Bootstrap（九）：组件--下拉菜单

1.效果样式

<div class="dropdown">
    <button class="btn btn-info" data-toggle="dropdown">
        <span class="glyphicon glyphicon-star"></span> 下拉菜单
        <span class="caret"></span>
    </button>
    
    <ul class="dropdown-menu">
        <li class="dropdown-header">操作</li> <!-- 设置标题 -->
        <li><a><span class="glyphicon glyphicon-plus"></span> 添加 </a></li>
        <li><a><span class="glyphicon glyphicon-trash"></span> 删除</a></li>
        <li><a><span class="glyphicon-list-alt"></span> 编辑</a></li>
        
        <li role="separator" class="divider"></li>  <!-- 设置分割线-->
        <li class="dropdown-header">工具</li>
        <li><a>复制</a></li>
        <li><a>剪切</a></li>
    </ul>

</div>