给恁全撂翻mv:关于asp三级联动菜单的问题

我正在做一个三级联动菜单，但在选择第二个菜单后没能把第一个菜单的sort_id提交过去，程序如下：

<%
dim sortid,gameid
sortid=request("sort_id")
gameid=request("gameid")
set rs=server.CreateObject("adodb.recordset")
sql="select * from sort"
rs.open sql,conn,1,1
strOption1 = "<option value=''>商品类别</option>"
do while not rs.eof
if cstr(rs("sort_id")) = cstr(sortid) then
strOption1 = strOption1 & "<option value='" & rs("sort_id") & "' selected>" & rs("sort_name") & "</option>"
else

strOption1 = strOption1 & "<option value='" & rs("sort_id") & "'>" & rs("sort_name") & "</option>"

end if
rs.movenext
loop

rs.close
strOption2 = "<option value=''>游戏名称</option>"
if sortid <> "" then
sql = "select * from gametypes where class=" & sortid

rs.open sql,conn,1,1

do while not rs.eof
if cstr(rs("id")) = cstr(gameid) then
strOption2 = strOption2 & "<option value='" & rs("id") & "' selected>" & rs("gamename") & "</option>"
else
strOption2 = strOption2 & "<option value='" & rs("id") & "'>" & rs("gamename") & "</option>"
end if
rs.movenext
loop
rs.close
end if
strOption3 = "<option value=''>游戏卡</option>"
if gameid <> "" then

sql = "select * from cardstype where gametypeid="&gameid
rs.open sql,conn,1,1

while not rs.eof
if cstr(rs("id")) = cstr(cardstypeid) then
strOption3 = strOption3 & "<option value='" & rs("id") & "' selected>" & rs("cardtypename") & "</option>"
else
strOption3 = strOption3 & "<option value='" & rs("id") & "'>" & rs("cardtypename") & "</option>"
end if

rs.movenext
wend
rs.close
end if
%>
<select onchange="changeb(this.value)" name="sort_id"><%=strOption1%></select>
<select onchange="change(this.value)" name="gameid"><%=strOption2%></select>
<select name="cardtypeid"><%=strOption3%></select>
<script language="javascript">
<!--
function changeb(sort_id){
location.assign("index123.asp?sort_id=" + sort_id);
}

function change(gameid){
location.assign("index123.asp?sort_id="&sort_id&"gameid=" + gameid);
}
-->
</script>

望大家多多指教