asp+access请问那位大侠知道那儿有三级连动的代码，网上一搜索就出来的那个，好象不能用，谢谢

<!--#include file="edu_inc/conn.asp"-->
<%
dim cid,coid
cid = request("cid") 'cid 大类id
coid = request("coid") 'coid 中类id
set rs=server.createobject("adodb.recordset")
sql = "select * from edu_c" '表一 大类表
rs.open sql,conn,1,1
strOption1 = "<option value='' selected >==请选择所属市局==</option>"
do while not rs.eof
if cstr(rs("id")) = cstr(cid) then
strOption1 = strOption1 & "<option value='" & rs("id") & "' selected>" & rs("c_name") & "</option>"
else

strOption1 = strOption1 & "<option value='" & rs("id") & "'>" & rs("c_name") & "</option>"