orelse

orelse
  If dr.RowState = DataRowState.Detached OrElse dr.RowState = DataRowState.Added Then
     e.Cancel = False
  Else
     e.Cancel = True
  End If
  => dr.RowState = DataRowState.Detached을 만족하면 dr.RowState = DataRowState.Added은 타지 않는다