<option selected value="s1">-- 请选择 --</option>
<!--默认选中-->
<option value="SC">SC</option>
<option value="BJ">BJ</option>
<option value="TJ">TJ</option></select><select id="s2">
<option selected>-- 请选择 --</option>
<!--默认选中，动态生成option --></select><script>
function move()
{
var s1=document.getElementById("s1")var s2=document.getElementById("s2")<!-- 获取一级和二级的属性-->
var add
if(s1.value=="SC")
{
add=new Array("CD","DZ","MY","NC")<!--比对value值，实现对应二级text值的动态生成-->
}else if(s1.value=="BJ")
{
add=new Array("HD","CY","WFJ")<!--比对value值，实现对应二级text值的动态生成-->
}else if(s1.value=="TJ")
{
add=new Array("TJG","TJ","TJY")<!--比对value值，实现对应二级text值的动态生成-->
}else if(s1.value=="s1")
{
add=new Array("请选择")
}
else
{
add=null<!--若没有就为空，当然不可能出现的-->
}
s2.length=0
for(var i=0i<add.lengthi++) { var ss=new Option() ss.text=add[i].split()[0]
s2.add(ss)
<!--把text值添加到二级select中，显示出来-->
}
}</script></body></html>
按说这种操作应该是后台程序来做，前端操作的话有点窒息，主要是数据量。。亲测有效，望采纳！
<!doctype html><html>
<head>
<meta charset="utf-8">
<title>无标题文档</title>
<link rel="stylesheet" type="text/css" href="CSS3/xuanxing.css" />
<script type="text/javascript" src="http://apps.bdimg.com/libs/jquery/1.6.4/jquery.js"></script>
</head>
<body>
<style>
select{ width:75px font-size:12px color:#000000 font-family:'宋体' margin:auto 0px}
#select0{ background:yellow}
.select{ background:#85e785}
</style>
<script>
$(document).ready(function(e) {
$("select#select0").change(function(){
var cc = $(this).find("option:selected").attr("class")
$(this).siblings("select").find("option").hide()
$(this).siblings("select").find("option."+cc).show()
$(this).siblings("select").find("option."+cc+":first").attr("selected","selected")
})
$("select.select").change(function(){
var cid = $(this).find("option:selected").index()
$(this).siblings("select.select").each(function(){
$(this).find("option").eq(cid).attr("selected","selected")
})
})
})
</script>
<div style="width: 400px height: 20px margin:0 auto word-spacing: 0px">
<select id="select0">
<option class="op0">10mm</option>
<option class="op1">20mm</option>
<option class="op2">40mm</option>
</select>
<select class="select">
<option class="op0">8n</option>
<option class="op0">12n</option>
<option class="op0">16n</option>
<option class="op1">24n</option>
<option class="op1">28n</option>
<option class="op1">32n</option>
<option class="op2">40n</option>
<option class="op2">44n</option>
</select>
<select class="select">
<option class="op0">70mm</option>
<option class="op0">110mm</option>
<option class="op0">150mm</option>
<option class="op1">230mm</option>
<option class="op1">270mm</option>
<option class="op1">310mm</option>
<option class="op2">390mm</option>
<option class="op2">430mm</option>
</select>
<select class="select">
<option class="op0">128mm</option>
<option class="op0">190mm</option>
<option class="op0">230mm</option>
<option class="op1">310mm</option>
<option class="op1">350mm</option>
<option class="op1">390mm</option>
<option class="op2">470mm</option>
<option class="op2">510mm</option>
</select>
<select class="select">
<option class="op0">ESA0810</option>
<option class="op0">ESA1210</option>
<option class="op0">ESA1610</option>
<option class="op1">ESA2410</option>
<option class="op1">ESA2810</option>
<option class="op1">ESA3210</option>
<option class="op2">ESA4010</option>
<option class="op2">ESA4410</option>
</select>
</div>
</body>
</html>
<!---->
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" " http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns=" http://www.w3.org/1999/xhtml" lang="gb2312">
<head>
<head>
<title>代码实例:级联菜单 </title>
<meta http-equiv="content-type" content="text/htmlcharset=gb2312" />
<meta name="author" content="枫岩,CNLei.y.l@gmail.com">
</head>
<body>
<select id="BigCate" name="BigCate" size="1" onchange="Redirect(this.options.selectedIndex)">
<option value="">全市</option>
<option value="">主城区</option>
<option value="">分公司</option></select>
<select id="SmlCate" name="SmlCate" size="1">
<option value="1">全市</option>
</select>
<script type="text/javascript">
<!--
var groups = document.getElementById("BigCate").options.length
var group = new Array(groups)
for (i = 0i <groupsi ++)
group[i] = new Array()group[0][0] = new Option("全市","ALL")group[1][0] = new Option("北部新区局","CJ0")
group[1][1] = new Option("杨家坪局","CY0")
group[1][2] = new Option("沙坪坝局","CP0")
group[1][3] = new Option("观音桥局","CG0")
group[1][4] = new Option("上清寺局","CS0")
group[1][5] = new Option("南坪局","CN0")group[2][0] = new Option("渝北电信公司","CF0")
group[2][1] = new Option("璧山电信公司","CA0")
group[2][2] = new Option("江津电信公司","CU0")
group[2][3] = new Option("合川电信公司","CK0")
group[2][4] = new Option("北碚电信公司","CI0")group[2][5] = new Option("巴南电信公司","CB0")
group[2][6] = new Option("永川电信公司","CH0")
group[2][7] = new Option("万州电信公司","WW0")
var temp = document.getElementById("SmlCate")
function Redirect(x){ for (m = temp.options.length-1m >0m --)
temp.options[m] = null
for (i = 0i <group[x].lengthi ++){
temp.options[i] = new Option(group[x][i].text,group[x][i].value)
alert(group[x][i].value)
}
temp.options[0].selected = true
}
//-->
</script></body>
</html>这个代码是入门的最佳辅助代码
