<div id="dropdown">
<p>請選擇城市</p>
<ul>
<li><a href="#" rel="2">北京</a></li>
<li><a href="#" rel="3">上海</a></li>
<li><a href="#" rel="4">武漢</a></li>
<li><a href="#" rel="5">廣州</a></li>
</ul>
</div>
<div id="result"></div>

<script type="text/javascript">
$(function(){
$("#dropdown p").click(function(){
var ul = $("#dropdown ul");
if(ul.css("display")=="none"){
ul.slideDown("fast");
}else{
ul.slideUp("fast");
}
});
$("#dropdown ul li a").click(function(){
var txt = $(this).text();
$("#dropdown p").html(txt);
var value = $(this).attr("rel");
$("#dropdown ul").hide();
$("#result").html("您選擇了"+txt+"，值為："+value);
});

});
</script>

#dropdown{width:186px; margin:100px auto; position:relative}
#dropdown p{width:150px; height:24px; line-height:24px; padding-left:4px; padding-right:30px; border:1px solid #a9c9e2; background:#e8f5fe url(arrow.gif) no-repeat rightright 4px; color:#807a62; cursor:pointer}
#dropdown ul{width:184px; background:#e8f5fe; margin-top:2px; border:1px solid #a9c9e2; position:absolute; display:none}
#dropdown ul li{height:24px; line-height:24px; text-indent:10px}
#dropdown ul li a{display:block; height:24px; color:#807a62; text-decoration:none}
#dropdown ul li a:hover{background:#c6dbfc; color:#369}
#result{margin-top:10px;text-align:center}