div?class="dropup?pull-right">
????<button?class="btn?btn-default?dropdown-toggle"?data-toggle="dropup"?id="dropmenus"?aria-haspopup="true"
????????????aria-expanded="true">下拉菜單</button>
????<ul?class="dropdown-menu?pull-right"?role="menu"?aria-labelledby="dropmenus"?id="menus">
????????<li?class="?dropdown-header"?role="presentation">第一部分頭</li>
????????<li?role="presentation"><a?href="#">蘋果</a></li>
????????<li?role="presentation"?class="active"><a?href="#">香蕉</a></li>
????????<li?role="presentation"><a?href="#">西瓜</a></li>
????????<li?class="dropdown-header"?role="presentation">第二部分頭</li>
????????<li?role="presentation"><a?href="#">西紅柿</a></li>
????????<li?role="presentation"><a?href="#">獼猴桃</a></li>
????????<li?role="presentation"><a?href="#">火龍果</a></li>
????</ul>
</div>