[RESOLVED] Varify Input

[aikidokid]

I have code to check the input for specific characters in a text box.
My code catches the incorrect characters, gives a warning, but after the user closes the msgbox, the incorrect character is still entered

I am sure this will be a simple solution but I can't figure it out at the moment.

I have tried the following code in the KeyDown, KeyPress and the KeyUp and I get the same problem each time.

Dim tmpDate As String
    tmpDate = txtMembership(Index).Text
    
    Select Case Index
        Case 11, 12, 13, 15
            Select Case KeyAscii
                Case 8          'backspace
                Case 47         '/forward slash
                Case 48 To 59   'numbers
                Case 127        'Delete key
                Case Else
                    MsgBox "You can only enter numbers and the ' / ' seperator when entering dates.", _
                            vbOKOnly + vbInformation, "Date Format"
                    'remove last character entered
                    'Exit Sub
                    txtMembership(Index).Text = tmpDate
            End Select
    End Select