如果 li里面的UL没有li就把她的class设为空

Question

<li class="expandable"> <a href="Title.aspx?mode=2&id=21&pid=5" target="main">C/C++</a>
                 <ul style="display: none; "> <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=36" target="main">新手乐园</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=37" target="main"> C语言</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=38" target="main"> C++ 语言</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=39" target="main">工具平台和程序库</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=40" target="main">模式及实现</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=41" target="main">其它技术问题</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=42" target="main">Qt开发</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=43" target="main">非技术区</a> </li>
                    
                 </ul>   
             </li> 
                
            <li class="expandable"> <a href="Title.aspx?mode=2&id=21&pid=6" target="main">Jboss</a>
                 <ul style="display: none; "> 
                 </ul>   
             </li> 
得到结果<li class="expandable"> <a href="Title.aspx?mode=2&id=21&pid=5" target="main">C/C++</a>
                 <ul style="display: none; "> <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=36" target="main">新手乐园</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=37" target="main"> C语言</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=38" target="main"> C++ 语言</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=39" target="main">工具平台和程序库</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=40" target="main">模式及实现</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=41" target="main">其它技术问题</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=42" target="main">Qt开发</a> </li>
                    <li ><a href="Title.aspx?mode=3&id=21&pid=5&ppid=43" target="main">非技术区</a> </li>
                    
                 </ul>   
             </li> 
                
            <li > <a href="Title.aspx?mode=2&id=21&pid=6" target="main">Jboss</a>
                 <ul style="display: none; "> 
                 </ul>   
             </li> function delClass()
{
  var   lis   =   document.getElementsByTagName('li'); 
  var i;
  var length;
          for( i=0; i<length;i++)  
         { 
                if(lis[i].getElementsByTagName('ul').length   ==   0)   
                {
                  lis[i].setAttribute('class',''); //不起效果
                }
          }
      }

Answer 1

简单点 
<li  class="expandable"> <a href="Title.aspx?mode=2&id=21&pid=6" target="main">Jboss</a>
                 <ul style="display: none; "> 
                 </ul>   
 </li> 
如果ul内不包含li  就把外面li的class去掉或改名

Answer 2

function delClass()
        {
          var   lis   =   document.getElementsByTagName('li'); 
          var i;
          var length;
          for( i=0; i<length;i++)  
         { 
                if(lis[i].getElementsByTagName('ul')[0].getElementsByTagName('li').length   ==   0)   
                {//是li下的ul的li的长度
                  lis[i].setAttribute('class',''); //不起效果
                 or lis[i].setAttribute('className',''); //不起效果
                }
          }
      }

Answer 3

<li class="expandable"> <a href="Title.aspx?mode=2&id=21&pid=6" target="main">Jboss</a>
  <ul style="display: none; ">  
  </ul>   
 </li>  如果ul内没有li就把ul节点去掉
变成
<li class="expandable"> <a href="Title.aspx?mode=2&id=21&pid=6" target="main">Jboss</a>
    
 </li>
用jquery怎么remove掉