dedecms 二级导航的实现代码

<ul id="topmenue"> 
    <li class="first" id="mn_portal"><a href="/" hidefocus="true" title="Portal">网站首页<span>Portal</span></a></li>   
{dede:channelartlist typeid={dede:field.typeid/}  
  <li id="mn_N5f30" onmouseover="t('{dede:field name='typeid'/}');" onmouseout="f('{dede:field name='typeid'/}');" name="{dede:field name='typeid'/}">  
   <a href="{dede:field name='typeurl'/}" [field:rel/] >{dede:field name='typename'/}</a>  
<ul id="snav" name="{dede:field.typeid/}">  
{dede:channel type='son' noself='yes'}  
  <li style="display:block;height:40px;margin:0;padding:0;clear:both;background:none;text-align:cnetent;line-height:40px;background:#F4FBF4;"><a href="[field:typelink /]" >[field:typename /]</a></li>  
{/dede:channel}  
</ul>
</li>  
{/dede:channelartlist}   
</ul>
<ul id="topmenue">
    <li class="first" id="mn_portal"><a href="/" hidefocus="true" title="Portal">网站首页<span>Portal</span></a></li>
{dede:channelartlist typeid={dede:field.typeid/}
  <li id="mn_N5f30" onmouseover="t('{dede:field name='typeid'/}');" onmouseout="f('{dede:field name='typeid'/}');" name="{dede:field name='typeid'/}">
   <a href="{dede:field name='typeurl'/}" [field:rel/] >{dede:field name='typename'/}</a>
 <ul id="snav" name="{dede:field.typeid/}">
 {dede:channel type='son' noself='yes'}
 <li style="display:block;height:40px;margin:0;padding:0;clear:both;background:none;text-align:cnetent;line-height:40px;background:#F4FBF4;"><a href="[field:typelink /]" >[field:typename /]</a></li>
 {/dede:channel}
  </ul>                                    
  </li>
{/dede:channelartlist}                                 
  </ul>

<script type="text/javascript"> 
    function t(id) { 
                var dul = document.getElementsByName(id); 
                var fu = dul[1];  
                    fu.style.display = "block"; 
                } 
    function f(id) { 
                var dul = document.getElementsByName(id); 
                var fu = dul[0];                 
                var lu = fu.childNodes[3]; 
                    lu.style.display = "none"; 
                } 
</script> 
<script type="text/javascript">
    function t(id) {
                var dul = document.getElementsByName(id);
                var fu = dul[1];
                    fu.style.display = "block";
                }
    function f(id) {
                var dul = document.getElementsByName(id);
                var fu = dul[0];               
                var lu = fu.childNodes[3];
                    lu.style.display = "none";
                }
</script>