aLi[i].className=""; this.className="active"; 这两句怎么解释啊?
<script type="text/javascript">
window.onload=function(){
var oUl1=document.getElementById("ul1");
var aLi=oUl1.getElementsByTagName("li");
var oDiv=document.getElementById("tab-list");
var aDiv=oDiv.getElementsByTagName("div");
for(var i=0;i<aLi.length;i++){
aLi[i].index=i;
aLi[i].onmouseover=function(){
for(var i=0;i<aLi.length;i++){
aLi[i].className="";
}
this.className="active";
for(var j=0;j<aDiv.length;j++){
aDiv[j].className="hide"
}
aDiv[this.index].className="show"
}
}
}
</script>