Quick Report Report 2.0

I could use some help I have to query a group of invoices that are all
marked "PRINT" then group the list of invoices by invoice number and force
anew page eveytime the invoice number changes in the group band. Can anyone
tell me how to do this with an expression. I can use an expression for
srting fields like Copy(CustName,1,1) to add a new page evertime the
CustName field changes in the first letter. This approach doesn't seem to
work in an Integer field. Even after taking the Invoice Number field and
using the expression field to cast the Integer as a string. If you know of a
good source of Expression explaination it would help also.

            Thanks Jon Stroh