javascript鼠标悬停改变背景颜色显示隐藏下级菜单

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实现的效果是当用户鼠标悬停在主菜单上的时候显示的是所有的信息当用户鼠标悬停在百货的时候显示百货的信息不显示其他的信息实现

实现动态的显示

<script type="text/javascript">
/*鼠标悬停的时候的样式*/
function onmouseOver(Obj,ulId){
/*获得当前ul节点下的子节点的数量*/
var length = document.getElementById("clearfix").getElementsByTagName("li").length;
var ulLength = document.getElementById("wrap").getElementsByTagName("ul").length;
//alert(ulLength);
for(i = 0;i<ulLength;i++){
document.getElementById("wrap").getElementsByTagName("ul")[i].style.display="none";
}
/*使用循环改变当前样式*/
for(i = 0;i<length;i++){
document.getElementById("clearfix").getElementsByTagName("li")[i].className="";
}
/*设置当前对象的样式*/
Obj.className="current";
document.getElementById(ulId).style.display="block";
}
</script>
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<dd class="title"><a href="product-view.html" target="_blank">法国德菲丝松露精品巧克力500g/盒</a></dd>
<dd class="price">￥108.0</dd>
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