For Each ctl As Control In Me.Controls
            If TypeOf ctl Is ComboBox Then
                Dim cb As ComboBox = DirectCast(ctl, ComboBox)
                With cb
                    If .ContextMenu Is Nothing AndAlso .ContextMenuStrip Is _
                      Nothing Then
                        .ContextMenu = cm
                    End If
                End With
            End If
        Next ctl