{ note this demo extracts icons from files containing icons
in the delphi 3 version the small icon extracted is displayed
as a crappy looking larger icon in the image
you cannot change the size of an icon without raising an exception
and so this is a puzzle you might want to solve if you are still
using delphi 3 and want to work with small icons}
{http://www.awitness.org/delphi_pascal_tutorial/index.html}
unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Label1: TLabel;
    Label2: TLabel;
    OpenDialog1: TOpenDialog;
    Edit1: TEdit;
    Image1: TImage;
    Image2: TImage;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    Procedure GetFilesIcon(FileName:string);
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}
procedure TForm1.Button1Click(Sender: TObject); {Open File to find icons}
begin
If OpenDialog1.Execute then begin
   Edit1.Text := '-1';
   GetFilesIcon(OpenDialog1.Filename);
end;
end;

procedure TForm1.Button2Click(Sender: TObject);  {get next icon}
begin
GetFilesIcon(OpenDialog1.FileName);
end;

Procedure TForm1.GetFilesIcon(FileName:string);
var
   IconPos : Cardinal;
   NumIcons, PLargeIcon, PSmallIcon : HICON;

begin
     try
        IconPos := StrToInt(Edit1.Text) + 1; {init -1 for pass 1}

        If FileExists(FileName) then begin

           Label1.Caption := 'Opened File : ' + FileName;

           {get total number of icons
           ExtractIconEx returns a small icon created even when only
           only one large icon actually exists in the file
           pass function -1 iconpos, and 0 0 for Var HIcons to signal function
	   that it is to return the number of icons in the file}
           PLargeIcon := 0; PSmallIcon := 0;
           NumIcons := ExtractIconEx(PChar(FileName), -1,
                               PLargeIcon, PSmallIcon, 1);

           If NumIcons = 0 then begin
              MessageDlg('No icons in this file' + chr(13) +
                 'Try finding extension in registry', mtError, [mbok],0);
              Label2.Caption := 'No Icons in this file';
           end
           else begin

              Label2.Caption := 'TOTAL NUMBER OF ICONS IN FILE : ' +
                IntToStr(NumIcons);

               {did user put invalid integer into edit position box?}
               {note Iconpos starts at zero, NumIcons starts at 1}
              If IconPos > NumIcons then IconPos := NumIcons -1;


              If NumIcons = IconPos then IconPos := 0; {rollover count}

              {now get large, small icons at icon pos}
              ExtractIconEx(PChar(FileName), IconPos,
                               PLargeIcon, PSmallIcon, 1);
              {if icon pic currently has handle then release resources first}
              If not (Image1.Picture.Icon.Empty) then
                        Image1.Picture.Icon.ReleaseHandle;
              If not (Image2.Picture.Icon.Empty) then
                        Image2.Picture.Icon.ReleaseHandle;
              Image1.Picture.Icon.Handle := PSmallIcon;
              Image2.Picture.Icon.Handle := PLargeIcon;

             {update edit box }
             Edit1.Text := IntToStr(IconPos);
           end; {num icons <> 0}
        end; {if fileexists}
     except  {string did not convert to integer}
        MessageDlg('Enter a valid integer in the Edit Box!',
                   mtError, [mbok], 0);
     end; {try}
end; {procedure}


procedure TForm1.FormCreate(Sender: TObject);
begin
        Form1.Caption := 'Extract Icons';
        Button1.Caption := 'Open file';
        Button2.Caption := 'Next Icon';
        Edit1.Text := '-1';
end;

end.