Problem separating request.form("value") from record ID

[David]

Hi,

I have an asp page which lists records.
Each record has an ID appended to it.
On the following edit page, I am trying to test against a certain
field value, if it is >0 then run the update, otherwise don't. The
problem is the data for testing is as follows:

Dim arrMetal
Dim iLoop
arrMetal=split(request.form("ID"), ", ")

For iLoop=0 to Ubound(arrMetal)

IF request.form("del_qty_" & arrMetal(iLoop)) > 0 THEN

Where del_qty is a number entered in the form, and arrMetal(iLoop) is
the records ID whilst in the loop on the edit page. When I try the
above if statement I get an error:

Microsoft VBScript runtime error '800a000d'

Type mismatch: '[string: ""]'

If I response.write request.form("del_qty_" & arrMetal(iLoop)), then I
get just the qty value without the ID printing.
How can I re-write my if statement to test the qty value ??? I have
tried using SPLIT on "_" but still the same .
I tried just request.form("del_qty"), but this gives me nothing.

Appreciate your help. I know why the error is there, but i'm not sure
how to get around it ?

Thanks

David