Dynamic combox n level

Function thutucdequycombo(idc,i)
	Set objConn = Server.CreateObject("ADODB.Connection")
	objConn.ConnectionString = strConnection
	objConn.Open 
	Set rs = Server.CreateObject("ADODB.RecordSet")
	rs.Open "SELECT * From rtm_area Where parent_aid = "&idc ,objconn, 1, 3
	k = rs.recordcount
	j=1
	while not rs.eof		
		 	IF rs("parent_aid") <> idc Then 
		 		Option_select_03 = Option_select_03 & "<option value=""" & rs("aid") & """>" & rs("name") & "</option>"
		 	Else
		 		Option_select_03 = Option_select_03 & "<option value=""" & rs("aid") & """>  " & rs("name") & "</option>"
		 	End IF		 	
			thutucdequycombo rs("aid"),rs("parent_aid") ' Goi lai chinh no - dequy	
	rs.movenext
	j=j+1
	'response.write"           "
	wend
End Function	
thutucdequycombo 0,0

aid: int
name: nvachar 50
parent_id: int

Leve1
   1-1
   1-2
Lever2
   2-1
   2-2
      2-3
.......