combox添加图标代码节选

首先: 这有现成的控件: TComboBoxEx, 没必要使用 TComboBox; 非要在 TComboBox 基础上添加, 也可以.

var
  Bits: array[0..3] of TBitmap;

procedure TForm1.FormCreate(Sender: TObject);
var
  i: Integer;
begin
  for i := 0 to Length(Bits)-1 do
  begin
    Bits[i] := TBitmap.Create;
    il1 .GetBitmap(i, Bits[i]);
    cbb1 .Items.Add(Format('Item %d', [i]));
  end;

  cbb1.Style := csOwnerDrawVariable;
  cbb1.ItemHeight := Bits[0].Height + 4;
  cbb1.ItemIndex :=2;
end;

procedure TForm1.FormDestroy(Sender: TObject);
var
  i: Integer;
begin
  for i := 0 to Length(Bits)-1 do
    Bits[i].Free;
end;

procedure TForm1.cbb1DrawItem(Control: TWinControl; Index: Integer;
  Rect: TRect; State: TOwnerDrawState);
begin
  cbb1 .Canvas.FillRect(Rect);
  cbb1 .Canvas.BrushCopy(Bounds(Rect.Left+2, Rect.Top+2, Bits[Index].Width, Bits[Index].Height),
                             Bits[Index],
                             Bounds(0, 0, Bits[Index].Width, Bits[Index].Height),
                             clBlack);
  cbb1.Canvas.TextOut(Rect.Left + 24, Rect.Top + 3, cbb1 .Items[Index]);

end;

end.