Is there a way to restrict a Masked Text Box to accept only certain letters? I know how to restrict for all letters. For example, the user should only input the letters "P", "R" or "N" ( or can be blank) in a particular Masked Text Box. I want to accomplish this without using a combo box. In case not,I tried to write an OR statement to test for the proper input but am having trouble.
If (MTXT_BillCode <> "P") Or (MTXT_BillCode <> "R") Or (MTXT_BillCode <> "N") Or (MTXT_BillCode <> " ") Then lbl_Message.Text = "Invalid Bill Code -- R,N,P Only" End If
Thank you very much in advance.