On Fri, 21 Nov 2008 13:40:15 GMT, "brydone via AccessMonster.com"
<u12683[ at ]uwe> wrote:
In the TrackingNumber's BeforeUpdate event write:
if not isnull(DLookup("TrackingNumber", "myTable", "TrackingNumber='"
& Me.TrackingNumber & "'")) then
Msgbox "Arrrcchhh, this number already exists"
Cancel = True
end if
Of course you may have to change the names to the ones in your
database. The strategy used here is to use DLookup to find a matching
record and if found (not isnull), then that's a problem. Also note how
I'm wrapping the tracking number in single quotes, which is required
for text lookups.
"Cancel=True" is important; it prevents the user from moving off of
this field until a trackingnumber that is not found is entered.
I'm sure you can figure out the rest, or post back with more
questions.
-Tom.
Microsoft Access MVP
[Quoted Text] >I have a database in Access 2003. Apart from the standard ID field, I have a
>field called TrackingNumber which is a text field for bar code numbers (text
>and numbers). I have indexed this field disallowing duplicates. This field
>takes input from a bar code scanner and then automatically moves onto the
>next field for entry. What I would like is that if a duplicate bar code is
>scanned in, a message should appear warning the inputter that this is a
>duplicate entry and the user be presented with and option of Cancel whick
>will clear the fiels of the scanned bar code and the other option to rescan
>the bar code. At the moment the standard VB error message is beng displayed
>with End and Debug as options. Obviousley, I don't want the inputter to have
>the debug option.
>
>Any help would really be appreciated.
>
>Many thanks......
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