Auto increment of invoice number (1 Viewer)

Hello team

i am in access so have less knowledge

i have primary key that is the code of the customer

i also have a Invoice no with a pattern of XXXXX/XX that is Text and controlled by the MASK

i want that when i enter a INVOICE Number, when i go to next or save the form and new form opens, that invoice number changed automatically

like 12345/01 when i go to next it will automatically changed to 12345/02 and so on , until i change the invoice number

it also allows me to change the invoice number when i need it to change.

please help me on this

Regards
Nasir

Cross posted https://www.utteraccess.com/forum/index.php?showtopic=2052588&hl=

@nashfaq please have a read here https://www.excelguru.ca/content.php?184

To provide an insight to your question, normally numbering sequences like this are inherited from a manual system that is trying to be replicated, and normally they aren't worth the effort.

Just have a unique invoice number. Unless you have a really compelling reason to continue with this scheme.

First:

XXXXX/XX that is Text

Click to expand...

When you want to do mathematical operations on data (like add 1) you need to store your data in types that handle that:
"23" + "1" = "231"
23 + 1 = 24

store numbers as numbers

Second, discrete pieces of data needs to be stored discretely. You've got a main invoice number XXXXX and then a sub-invoice number XX. Those should be 2 different fields in your table.

Third, all the above is moot, I agree with Minty. Use an autonumber and call it a day. Numbers aren't mystical entities. Often, as in this case, they simply help reference something. There's no gain from having some special algorithm to produce your invoice numbers.