How can make Subform with autofiling part of one field?

[aonsu209]

Can you help me how can I make a field which to take part of the value from another field to have constant text and text for adding?


For example on the pic below I have the project number and under each project number there is subform with document number which consist the year and the project number plus constant "C" (for calculation) and the number of the calculation which I want to fill.

[ItsMe]

VBA behind a bound form could concatenate values. Not positive which values you are trying to concatenate but...

Me![Document Name] = Mid(Me![Project Number], InStr(Me![Project Number], "-") + 1) & Constant & Me![Only to fill in]