二级联动和文本框赋值的问题


 <script language = "JavaScript">
var onecount2;
onecount2=0;
subcat2 = new Array();subcat2[0] = new Array("诸暨市","1","1");subcat2[1] = new Array("上虞市","1","2");subcat2[2] = new Array("嵊州市","1","3");subcat2[3] = new Array("新昌市","1","4");subcat2[4] = new Array("绍兴市","1","5");subcat2[5] = new Array("绍兴县","1","6");
subcat2[6] = new Array("扬州市","2","1");subcat2[7] = new Array("徐州","2","2");
onecount2=8;
function changelocation2(locationid)
    {
    document.aspnetForm.ccityid.length = 0; 
    var locationid=locationid;
    var i;
    for (i=0;i < onecount2; i++)
        {
            if (subcat2[i][1] == locationid)
            { 
             document.aspnetForm.ccityid.options[document.aspnetForm.ccityid.length] = new Option(subcat2[i][0], subcat2[i][2]);
            }        
        }
    }    
</script> <script>
function changeselect()
{
if(this.aspnetForm.cprovinceid.selected)
{
this.aspnetForm.ctl00_ContentPlaceHolder1_school_name.value="默认";
}
else
{
alert(this.aspnetForm.cprovinceid.value);
alert(this.aspnetForm.ccityid.value);
this.aspnetForm.school_name.value=this.aspnetForm.cprovinceid.value+this.aspnetForm.ccityid.value;
}
return false;
}
</script>  
<form name="aspnetForm">
<select name="cprovinceid" size="1" id="cprovinceid" onChange="changelocation2(document.aspnetForm.cprovinceid.options[document.aspnetForm.cprovinceid.selectedIndex].value)">
<option selected value="">-请选择-</option>
 
      <option value="1">浙江省</option>
  <option value="2">江苏省</option>
              </select>
              省 
              <select name="ccityid" onchange="changeselect()">               <option selected value="">-请选择-</option>
              </select>
      市       
                <input id="school_name" ></input>
</form>代码修改为纯html测试了，没什么问题啊，选择第一个后，再选择第二个，两个select的value都可以获取到，输出为12，22之类的