Characters Validation (works with any combination)

Const sValidLetter As String = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
Const sValidNumeric As String = "0123456789"
Const sValidFrench As String = "TOFaTG(÷v·t"

Public Enum eCaseCheck
eUPPER = 0
eLOWER = 1
eBOTH = 2
End Enum

Private Sub Text1_KeyPress(KeyAscii As Integer)
'Check with space, letters and french accents no case sensitivity
If Not isValidChar(KeyAscii, Chr(32) + sValidLetter + sValidFrench, eBOTH) Then KeyAscii = 0
End Sub

Public Function isValidChar(KeyAscii As Integer, sValidKey As String, iCheck As eCaseCheck) As Boolean

'Backspace or Enter
If KeyAscii = 8 Or KeyAscii = 13 Then
isValidChar = True
Exit Function
End If

If iCheck = eLOWER Then
isValidChar = InStr(1, LCase(sValidKey), Chr(KeyAscii)) > 0
ElseIf iCheck = eUPPER Then
isValidChar = InStr(1, UCase(sValidKey), Chr(KeyAscii)) > 0
Else
isValidChar = InStr(1, UCase(sValidKey), UCase(Chr(KeyAscii))) > 0
End If

End Function