Dear Naomi

May you did not read my qeustion carefully.

Text1 has Numeric data type but in property sheet it has no Input mask or format.

If user writes 1234 then comma automatically displayed as 1,234 (before pressing enter)
If user write 12345 then comma automatically displayed as 12,345 (before pressing enter)
If user write 123456 then comma automatically displayed as 1,23,456 (before pressing enter)
If user write 1234567 then comma automatically displayed as 12,34,567 (before pressing enter)

and so on as 12,34,56,789

I hope now the point is more clear