How to make an associated drop-down menu?

<form name=f1 METHOD="POST">

<%

OpenDB objConn, "xxxx"

Set RSClass = ("select * from class Order by fldClass")

If Then

"oh,No record!<BR>"

Else

"<select NAME=""class"" style=""FONT-SIZE: 9pt"" SIZE=10"

" ONCHANGE=""classselected(this);"" >"

sjavascript = "function classselected(elem){" &_

vbCrlf

"for (var i = document.; i >= 0; i--){" 

"document.[i] = null;" 

vbCrlf

Do Until

If sLastClass <> RSClass("fldClass") Then

sLastClass = RSClass("fldClass")

"<OPTION VALUE=" & RSClass("fldID") & ">" & sLastClass & "</OPTION>"

sjavascript = sjavascript & "}" 

"if ([].value=="

RSClass("fldID") & "){"

End If

sjavascript = sjavascript

"document.[document."

"] = new Option('"

RSClass("fldSort") & "','" & RSClass("fldID") & "');"

vbCrlf

Loop

 

"</select>"

"<select NAME=""sort"" style=""FONT-SIZE: 9pt"" SIZE=10>"

"<OPTION>Please select</OPTION>"

"</select>"

　

sjavascript = sjavascript  & "}"  & "}"

 

"<SCR" & "IPT LANGUAGE=""javascript"">"

sjavascript  & "</SCR" & "IPT>"

 

End If

Set RSClass = Nothing

%>

</form>