DEMO----------有问题请指出
代码截错了，再来一遍
<!doctype html>
<html>
<head>
<meta charset="UTF-8">
<title>下拉菜单</title>
<style type="text/css">
body,ul,li{ margin:0; padding:0; font-size:13px;}
ul,li{list-style:none;}
#divselect{width:186px; margin:80px auto; position:relative; z-index:10000;}
#divselect cite{width:150px; height:24px;line-height:24px; display:block; color:#807a62; cursor:pointer;font-style:normal;
padding-left:4px; padding-right:30px; border:1px solid #333333; }
#divselect ul{width:184px;border:1px solid #333333; background-color:#ffffff; position:absolute; z-index:20000; margin-top:-1px; display:none;}
#divselect ul li{height:24px; line-height:24px;}
#divselect ul li a{display:block; height:24px; color:#333333; text-decoration:none; padding-left:10px; padding-right:10px;}
</style>
<script type="text/javascript">
window.onload=function(){
var box=document.getElementById('divselect'),
title=box.getElementsByTagName('cite')[0],
menu=box.getElementsByTagName('ul')[0],
as=box.getElementsByTagName('a'),
index=-1;
// 点击三角时
title.onclick=function(event){
menu.style.display="block";
event.stopPropagation();
for(var j=0;j<menu_li.length;j++){
menu_li[j].style.backgroundColor = "#fff";
}
}
document.onkeyup=function(event){
if(event.keyCode==38){
index--;
if(index<0){
index=menu_li.length;
}
for(var j=0;j<menu_li.length;j++){
menu_li[j].style.backgroundColor = "#fff";
}
menu_li[index].style.backgroundColor = "#ddd";
}
else if(event.keyCode==40){
index++;
if(index>=menu_li.length){
index = 0;
}
for(var j=0;j<menu_li.length;j++){
menu_li[j].style.backgroundColor = "#fff";
}
menu_li[index].style.backgroundColor = "#ddd";
}
else if(event.keyCode==13){
var a = menu_li[index].getElementsByTagName("a")
title.innerHTML=a[0].innerHTML;
menu.style.display="none";
}
}
// 滑过滑过、离开、点击每个选项时
// 执行脚本
var menu_li;
var i;
menu_li = menu.getElementsByTagName("li");
for(i=0;i<menu_li.length;i++){
menu_li[i].index = i;
menu_li[i].onmouseover=function(){
for(var j=0;j<menu_li.length;j++){
menu_li[j].style.backgroundColor = "#fff";
}
this.style.backgroundColor = "#ddd";
index = this.index;
}
menu_li[i].onmouseleave=function(){
this.style.backgroundColor = "#fff";
index = this.index;
}
menu_li[i].onclick=function(){
var a = menu_li[index].getElementsByTagName("a")
title.innerHTML=a[0].innerHTML;
menu.style.display="none";
}
}
}
</script>
</head>
<body>
<div id="divselect">
<cite>请选择分类</cite>
<ul>
<li id="li"><a href="javascript:;" selectid="1">ASP开发</a></li>
<li><a href="javascript:;" selectid="2">.NET开发</a></li>
<li><a href="javascript:;" selectid="3">PHP开发</a></li>
<li><a href="javascript:;" selectid="4">Javascript开发</a></li>
<li><a href="javascript:;" selectid="5">Java特效</a></li>
</ul>
</div>
</body>
</html>