You will need to filter out the wrong KeyDown events depending on the
position in the textbox.
There might be a more clever way to do this with regular expressions, but
something like this will
get you on the right track:

Private Sub TextBox1_KeyDown(ByVal KeyCode As MSForms.ReturnInteger, _
ByVal Shift As Integer)

If KeyCode < 8 And KeyCode < 9 And KeyCode < 13 And _
KeyCode < 35 And KeyCode < 36 And KeyCode < 37 _
And KeyCode < 39 And KeyCode < 46 Then
Select Case TextBox1.SelStart
Case 0, 1, 2, 4, 5, 6
If IsAlpha(Int(KeyCode)) = False Then
KeyCode = 0
Exit Sub
End If
Case 3, 7
If KeyCode < 191 Or Shift < 0 Then
KeyCode = 0
Exit Sub
End If
Case 8, 9, 10
If IsNumeric(Int(KeyCode)) = False Then
KeyCode = 0
Exit Sub
End If
Case Else
KeyCode = 0
Exit Sub
End Select
End If

End Sub

Function IsAlpha(iKeyCode As Integer) As Boolean
If iKeyCode 64 And _
iKeyCode < 91 Then
IsAlpha = True
End If
End Function

Function IsNumeric(iKeyCode As Integer) As Boolean
If iKeyCode 95 And _
iKeyCode < 106 Then
IsNumeric = True
End If
End Function

Just fiddle the numbers till you get it as you want.


RBS


"BadgerMK" wrote in
message ...

Hi All

I'm looking to limit an entry into a text box in a userform to
AAA/AAA/NNN

A=Alpha
N=Numeric

Any help greatly appreciated


--
BadgerMK
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