I would like for my datagridview to automatically fill in the column's next row with the previous entry + 1 letter. So say my datagrid is like this:

ID NextField
15-3A xxxxx
15-3B xxxxx
15-3C xxxxx

Everything is working fine if I type it in but would be nice if the user didn't have to type this each time and just have it fill in the next consecutive ID automatically when you press down to start a new row. Also i need it to work no matter what gets typed in... so if I make another ID 15-4A it will start filling in 15-4B etc. on each new row.

Any Ideas?