Extraire l'icone d'une application

uses shellApi;
procedure TForm1.Button1Click(Sender: TObject);
var
icon:TIcon;
begin
if Opendialog1.Execute then
begin
icon:=TIcon.Create;
icon.Handle:=ExtractIcon(hInstance,PChar(Opendialog1.filename),0);
DrawIcon(Form1.Canvas.Handle,10,10,icon.Handle);
icon.Free;
end;
end;