32.Bootstrap(中文教程)元件：Dropdown:分离式下拉式选单

ㄧ.分离式下拉式选单

<div class="component" id="demo">  <div class="btn-group">    <a href="#" class="btn btn-success">Dropdown</a>    <button class="btn btn-success dropdown-toggle dropdown-toggle-split" data-toggle="dropdown">      <span class="sr-only">Dropdown</span>     </button>    <div class="dropdown-menu">      <div class="dropdown-header">Web language</div>      <a href="#" class="dropdown-item">HTML</a>      <a href="#" class="dropdown-item">CSS</a>      <a href="#" class="dropdown-item">JavaScript</a>      <div class="dropdown-divider"></div>      <a href="#" class="dropdown-item">More</a>    </div>  </div></div>.demo.component{  padding: 50px;}

重点：

1.将按钮上的a跟button调换
2.button添加.dropdown-toggle-split
3.button在添加子元素span.sr-only，将内容的文字放入是不会显示文字的
4.最后将.Dropdown改成.btn-group

codepen
参考：bootstrap4