求高手 看怎么样能得到links[last].className=名称+变量

<div class="dh_cas">
<ul>
<div id="navi">
<li class="sm1"><a href="index.html" _fcksavedurl="index.html">首&nbsp;&nbsp;页</a></li>
<li class="sm2"><a href="index1.html" _fcksavedurl="index1.html">阿罗美食</a></li>
<li class="sm3"><a href="index2.html" _fcksavedurl="index2.html">番茄故事</a></li>
<li class="sm4"><a href="index3.html" _fcksavedurl="index3.html">番茄行动</a></li>
<li class="sm5"><a href="index4.html" _fcksavedurl="index4.html">资讯信息</a></li>
<li class="sm6"><a href="index5.html" _fcksavedurl="index5.html">加入我们</a></li>
<li class="sm7"><a href="index6.html" _fcksavedurl="index6.html">连锁门店</a></li>
</div>
</ul>
</div>
<script type="text/javascript" language="javascript">
var nav = document.getElementById("navi");
var links = nav.getElementsByTagName("li");
var lilen = nav.getElementsByTagName("a"); //判断地址
var currenturl = document.location.href;
var last = 0;
for (var i=0;i<links.length;i++)
{
var linkurl = lilen[i].getAttribute("href");
if(currenturl.indexOf(linkurl)!=-1)
{
last = i;
}
}
links[last].className = "dh_cas ul li.sm1:hover" ; //高亮代码样式
</script>
links[last].className = "dh_cas ul li.sm1:hover" ;
想得到以下结果
links[last].className = "返回我样式表中对应的dh_cas ul li.sm1:hover到dh_cas ul li.sm7:hover的值 对应我li代码中的样式位置" ;