<div id="topmenu" class="0" cid="23">
<a href='/ChannelID/23'>产品中心</a>
</div>
<div id="topmenu" class="23" cid="25">
<a href='/ChannelID/25'>智能设备</a>
</div>
<div id="topmenu" class="25" cid="57">
<a href='/ChannelID/57'>无人机</a>
</div>
<div id="topmenu" class="0" cid="13">
<a href='/ChannelID/13'>新闻频道</a>
</div>
<div id="topmenu" class="13" cid="15">
<a href='/ChannelID/15'>新闻一</a>
</div>
<div id="topmenu" class="15" cid="57">
<a href='/ChannelID/57'>新闻一(1)</a>
</div>
想实现的形式如下
div id="topmenu" class="0" cid="23">
<a href='/ChannelID/23'>产品中心</a>
<ul><li>
<div id="topmenu" class="23" cid="25">
<a href='/ChannelID/25'>智能设备</a>
<ul><li>
<div id="topmenu" class="25" cid="57">
<a href='/ChannelID/57'>无人机</a>
</div>
</li></ul>
</div>
</li></ul>
</div>
<div id="topmenu" class="0" cid="13">
<a href='/ChannelID/13'>新闻频道</a>
<ul><li>
<div id="topmenu" class="13" cid="15">
<a href='/ChannelID/15'>新闻一</a>
<ul><li>
<div id="topmenu" class="15" cid="57">
<a href='/ChannelID/57'>新闻一(1)</a>
</div>
</li></ul>
</div>
</li></ul>
</div>