procedure TForm1.DBGrid_Professional1DrawColumnCell(Sender: T;

  const Rect: TRect; DataCol: Integer; Column: TColumn;

  State: TGridDrawState);
var
  test1: Real;

  RowNo: Integer;

  BColor:Tcolor;
begin
 with (Sender as TDBGrid) do
 begin
 if (gdSelected in State) then
 begin
 // color of the focused row
      Canvas.Brush.Color := clblue;

    end
 else
 begin
 // get the actual row number
      rowno := DataSource1.DataSet.RecNo;

      // odd or even ?
      test1 := (RowNo / 2) - trunc(RowNo / 2);

      // If it"s an even one...
 if test1 = 0 then
 begin
        BColor := clWhite

      end
 // ...else it"s an odd one
 else
 begin
        BColor := clYellow;

      end;

      Canvas.Brush.Color := BColor;

      // font color always black
      Canvas.Font.Color := clBlack;

    end;

    Canvas.FillRect(Rect);

    // manualy output the text
    Canvas.TextOut(Rect.Left + 2, Rect.Top + 1, Column.Field.AsString);

  end

end;

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