Private Sub txtPhone_Validate(Cancel As Boolean)
   Dim strTemp As String
   Dim strPhone As String
   Dim strExtension As String
   Dim intResult As Integer
   
   Const DefaultAreaCode = "703"
   '
   ' Remove all the grouping characters for
   ' now. We'll add them back in later.
   '
   strTemp = Replace(txtPhone, "(", "")
   strTemp = Replace(strTemp, ")", "")
   strTemp = Replace(strTemp, "-", "")
   strTemp = Replace(strTemp, " ", "")
   strTemp = Replace(strTemp, "X", "x")
   
   '
   ' Break up the digits into the number and
   ' the extension, if any.
   '
   intResult = InStr(1, strTemp, "x", vbTextCompare)
   If intResult > 0 Then
      strExtension = Mid(strTemp, intResult + 1)
      strPhone = Left(strTemp, intResult - 1)
   Else
      strPhone = strTemp
   End If
   
   If Left(strPhone, 1) = "1" Then
      strPhone = Mid(strPhone, 2)
   End If
   
   If Len(strPhone) <> 7 And Len(strPhone) <> 10 Then
      MsgBox "Please enter a valid telephone number.", vbExclamation
	Cancel = True
      Exit Sub
   End If
   
   '
   ' Prepend the default area code
   '
   If Len(strPhone) = 7 Then
      strPhone = DefaultAreaCode & strPhone
   End If
   
   '
   ' Build the new phone number
   '
   txtPhone = "(" & Left(strPhone, 3) & ") " _
      & Mid(strPhone, 4, 3) & "-" _
      & Right(strPhone, 4)
   
   '
   ' Add the extension, if any
   '
   If strExtension <> "" Then
      txtPhone = txtPhone & " x" & strExtension
   End If
   
End Sub