ASP cascade menu

<% @ Language = "VBScript" codePage = "936" %>
<! -- # Include file = "Connections/connmenu. asp" -->

<! -- Open two tables -->
<%
Set RS1 = server. Createobject ("ADODB. recordset ")
Sql1 = "select * from main"
Rs1.open sql1, mm_connmenu_string, 1, 3
Set rs2 = server. Createobject ("ADODB. recordset ")
Sql2 = "select * From sub"
Rs2.open sql2, mm_connmenu_string, 1, 3

%>
<Form name = "form1">
<! -- Create menu 1 -->
<Select name = "mainmenu" size = "1" onchange = "Redirect (this. Options. Value)">
<Option value = 0> select ...... </Option>
<% While not rs1.eof %>
<Option value = "<% = RS1 (" main_id ") %>"> <% = RS1 ("main_name") %> </option>
<% Rs1.movenext
Wend %>
</SELECT>
<! -- Create menu 2 -->
<Select name = "submenu" size = "1">
<Option value = 0> select </option>
</SELECT>

</Form>
<! -- The following is a specific script statement -->
<SCRIPT>
<! --

VaR temp = Document. form1.submenu
Function redirect (x ){

VaR I
I = 0
For (var m = temp. Options. Length-1; m> 0; m --)
Temp. Options [m] = NULL

<% While not rs2.eof
%>
CNT = <% = rs2 ("main_id") %>

If (CNT = x ){
Temp. Options [I] = New Option ("<% = rs2 (" sub_name ") %>", "<% = rs2 (" sub_id ") %> ")
I = I + 1}
<%
Rs2.movenext
Wend %>

}

// -->
</SCRIPT>