有2个下拉列表框，我要实现当第1个下拉列表的被选择项改变时，第二个的内容也跟着改变。下面是我的代码，谁能告诉我我哪儿错了？
我的javascript代码是这样的：
<script type= "text/javascript ">
function changeSort(){
var msg = " <option value= 'hardware '> 硬件产品 </option> <option value= 'soft '> 硬件产品 </option> ";
var selected = document.getElementById( "sort ").selectedIndex;
var sort = document.getElementById( "jtsort ");
if(selected==1){
msg = " <option value= 'hardware '> 软件产品 </option> <option value= 'soft '> 软件产品 </option> ";
}
sort.innerHTML = msg;
}
</script>
下面是2个下拉列表框：
<select name= "productsort " id= "sort " onchange= "changeSort() ">
<option value= "hardware "> 硬件产品 </option>
<option value= "soft "> 软件产品 </option>
</select>
<select name= "jtsort " id= "jtsort ">
<option value= "hardware "> 硬件产品 </option>
<option value= "soft "> 软件产品 </option>
</select>
------解决方案--------------------
我做了一个，给你看看呀。
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN ">
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META NAME= "Generator " CONTENT= "EditPlus ">
<META NAME= "Author " CONTENT= " ">
<META NAME= "Keywords " CONTENT= " ">
<META NAME= "Description " CONTENT= " ">
<script type= "text/javascript ">
function changeSort(){
//var msg = " <option value= 'hardware '> 硬件产品 </option> <option value= 'soft '> 硬件产品 </option> ";
var selected = document.getElementById( "sort ").selectedIndex;
var sort = document.getElementById( "jtsort ");
if(selected==1){
var ops = sort.options;
for(var i = 0;i <ops.length;i++){
var option = ops[i];
option.value = "soft ";
option.innerHTML = "软件产品 ";
}
}else{
var ops = sort.options;
for(var i = 0;i <ops.length;i++){
var option = ops[i];
option.value = "hardware ";
option.innerHTML = "硬件产品 ";
}
}
}
</script>
</HEAD>
<BODY>
<select name= "productsort " id= "sort " onchange= "changeSort() ">
<option value= "hardware "> 硬件产品 </option>
<option value= "soft "> 软件产品 </option>