Bootstrap 组件之按钮（二）

<div class="btn-group" role="group">
<button type="button" class="btn btn-default">left</button>
<button type="button" class="btn btn-default">middle</button>
<button type="button" class="btn btn-default">right</button>
</div> 

<div class="btn-toolbar" role="toolbar">
<div class="btn-group" role="group">...</div>
<div class="btn-group" role="group">...</div>
<div class="btn-group" role="group">...</div>
</div> 

<div class="btn-group bt-group-*">
<button class="btn btn-default">left</button>
<button class="btn btn-default">middle</button>
<button class="btn btn-default">right</button>
</div> 

<div class="btn-group" role="btn-group">
<button class="btn btn-default">按钮1</button>
<button class="btn btn-default">按钮2</button>
<div class="btn-group" role="btn-group">
<button class="btn btn-default dropdown-toggle" data-toggle="dropdown">下拉 
<span class="caret"></span>
</button>
<ul class="dropdown-menu">
<li><a>项目一</a></li>
<li><a>项目二</a></li>
</ul>
</div>
</div> 

<div class="btn-group-vertical" role="btn-group">
...
</div> 

<div class="btn-group btn-group-justified" role="group">
<div class="btn-group" role="group">
<button class="btn btn-default">left</button>
</div>
<div class="btn-group" role="group">
<button class="btn btn-default">left</button>
</div>
<div class="btn-group" role="group">
<button class="btn btn-default dropdown-toggle" data-toggle="dropdown">right <span class="caret"></span></button>
<ul class="dropdown-menu">
<li><a>item1</a></li>
<li><a>item2</a></li>
</ul>
</div>
</div> 

<div class="btn-group" role="group">
<button class="btn btn-default dropdown-toggle" data-toggle="dropdown">
button <span class="caret"></span>
</button>
<ul class="dropdown-menu">
<li><a href="">item1</a></li>
<li><a href="">item2</a></li>
</ul>
</div> 

<div class="btn-group">
<button class="btn btn-default">button</button>
<button class="btn btn-default dropdown-toggle" data-toggle="dropdown"><span class="caret"></span></button>
<ul class="dropdown-menu">
<li><a href="">item1</a></li>
<li><a href="">item2</a></li>
</ul>
</div> 

<div class="btn-group">
<button class="btn btn-default dropdown-toggle btn-*" data-toggle="dropdown">button <span class="caret"></span></button>
<ul class="dropdown-menu">
<li><a href="">item1</a></li>
<li><a href="">item2</a></li>
</ul>
</div> 

<div class="btn-group dropup">
<button class="btn btn-default dropdown-toggle btn-lg" data-toggle="dropdown">button <span class="caret"></span></button>
<ul class="dropdown-menu">
<li><a href="">item1</a></li>
<li><a href="">item2</a></li>
</ul>
</div>