<!DOCTYPE html >
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>模拟select控件</title>
<style>
html,body{height:100%;overflow:hidden;}
body,div,form,h2,ul,li{margin:0;padding:0;}
ul{list-style-type:none;}
body{background:#23384e; }
#search,#search form,#search .box,#search .select,#search a{background:url(search.jpg) no-repeat;}
#search,#search .box,#search form{height:34px;}
#search{position:relative;350px;margin:10px auto;}
#search .box{background-position:right 0;}
#search form{background-repeat:repeat-x;background-position:0 -34px;margin:0 20px 0 40px;}
#search .select{float:left;color:#fff;190px;height:22px;cursor:pointer;margin-top:4px;line-height:22px;padding-left:10px;background-position:0 -68px;}
#search a{float:left;80px;height:24px;color:#333;letter-spacing:4px;line-height:22px;text-align:center;text-decoration:none;background-position:0 -90px;margin:4px 0 0 10px;}
#search a:hover{color:#f60;background-position:-80px -90px;}
#search .sub{position:absolute;top:26px;left:40px;color:#fff;198px;background:#2b2b2b;border:1px solid #fff;display:none;}
#search .sub li{height:25px;line-height:24px;cursor:pointer;padding-left:10px;margin-bottom:-1px;border-bottom:1px dotted #fff;}
#search .sub li:hover{background:#8b8b8b;}
</style>
</head>
<body>
<div id="search">
<div class="box">
<form>
<span id="select" class="select">请选择游戏名称</span>
<a href="javascript:;">搜索</a>
</form>
</div>
<ul id="sub" class="sub">
<li>地下城与勇士</li>
<li>魔兽世界（国服）</li>
<li>魔兽世界（台服）</li>
<li>热血江湖</li>
<li>大话西游II</li>
<li>QQ幻想世界</li>
</ul>
</div>
</body>
</html>
<script src="public.js"></script>
<script>
// 点击 span 显示 列表 ul
// 点击文档 document ,隐藏 列表ul
// 点击每一个li ， 将当前li的 内容 显示到 span中
var oUl = $id("sub");
var list = oUl.children;
//点击span时，显示列表
$id("select").onclick = function( e ){
//兼容写法
var e = e || event;
e.stopPropagation() ? e.stopPropagation() : e.cancelBubble = true;
oUl.style.display = "block";
}
//点击 文档document时，隐藏列表
document.onclick = function(){
oUl.style.display = "none";
}
//点击每个li时，内容显示到span中
for( var i = 0 ; i < list.length ; i++ ){
list[i].onclick = function( e ){
//兼容写法
var e = e || event;
e.stopPropagation() ? e.stopPropagation() : e.cancelBubble = true;
$id("select").innerHTML = this.innerHTML;
//当某个li的内容显示到span中后，让列表隐藏
oUl.style.display = "none";
}
}
</script>