[Rosenkrantz]

Код:

unit ilUnit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ImgList, ExtCtrls, StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    Image1: TImage;
    ImageList1: TImageList;
    procedure Button1Click(Sender: TObject);
  private
    FImageIndex: Integer;
    procedure SetImageIndex(const Value: Integer);
    { Private declarations }
  public
    { Public declarations }
    constructor Create(AOwner: TComponent); override;

    property ImageIndex: Integer read FImageIndex write SetImageIndex;
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

{ TForm1 }

procedure TForm1.Button1Click(Sender: TObject);
begin
  if ImageIndex < ImageList1.Count - 1 then
    ImageIndex := ImageIndex + 1
  else
    ImageIndex := 0;
end;

constructor TForm1.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);

  ImageIndex := -1;
end;

procedure TForm1.SetImageIndex(const Value: Integer);
var
  B: TBitmap;
begin
  If FImageIndex <> Value then begin
    if (Value >= 0) and (Value < ImageList1.Count) then begin
      FImageIndex := Value;

      B := TBitmap.Create;

      ImageList1.GetBitmap(FImageIndex, B);
      Image1.Picture.Bitmap := B;
      Image1.Refresh;
      Image1.Visible := True;

      B.Free;
    end else begin
      FImageIndex    := -1;
      Image1.Visible := False;
    end;
  end;
end;

end.