有没有人会做下拉式菜单呀?(在线等)

[myhorsefsy]

有的话,请教教我.我不会做呀.

[lxhvc]

<form name="form1" method="post">
<select id="s1" name="s1"></select><select id="s2" name="s2"></select><select id="s3" name="s3"></select><select id="s4" name="s4"></select>
</form>

<script language="javascript" >
function CLASS_LIANDONG_YAO(array, select)
{
this.array=array;
this.indexName='';
this.obj='';

this.subSelectChange=function(id,subid)
{
var obj1=document.getElementById(id);
var obj2=document.getElementById(subid);
var objName=this.toString();
var me=this;
obj1.onchange=function()
{
me.optionChange(this.options[this.selectedIndex].value,obj2.id)
}
}
this.firstSelectChange=function(indexName,id)
{
this.obj=document.getElementById(id);
this.indexName=indexName;
this.optionChange(this.indexName,this.obj.id)
}
this.optionChange=function (indexName,id)
{
var obj1=document.getElementById(id);
var me=this;
obj1.length=0;
obj1.options[0]=new Option("请选择",'');
for(var i=0;i<this.array.length;i++)
{
if(this.array[i][1]==indexName)
{
obj1.options[obj1.length]=new Option(this.array[i][2],this.array[i][0]);
}
}
}

this.firstSelectChange("root",select[0]);
for(var i=1;i<select.length;i++)
{
this.subSelectChange(select[i-1],select[i]);
}

}

var array=new Array();
array[0]=new Array("华南地区","root","华南地区");
array[1]=new Array("华北地区","root","华北地区");
array[2]=new Array("上海","华南地区","上海");
array[3]=new Array("广东","华南地区","广东");
array[4]=new Array("徐家汇","上海","徐家汇");
array[5]=new Array("普托","上海","普托");
array[6]=new Array("广州","广东","广州");
array[7]=new Array("湛江","广东","湛江");
array[8]=new Array("湛江1","湛江","湛江1");
array[9]=new Array("湛江2","湛江","湛江2");
array[10]=new Array("广州1","广州","广州1");
array[11]=new Array("广州2","广州","广州2");

var select = new Array("s1","s2","s3","s4");

var liandong=new CLASS_LIANDONG_YAO(array, select)
</script>