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Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)
  Select Case KeyCode
    Case vbKeyLeft
       If Form.ActiveControl.Name = Form.Controls( 0 ).Name Then
         'Находимся на первой колонке.
         KeyCode =  0 : End If
    Case vbKeyRight
       If Form.ActiveControl.Name =
         Form.Controls(Form.Controls.Count -  2 ).Name Then
         'Находимся на последней колонке.
         KeyCode =  0 : End If
    Case Else
  End Select
End Sub
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