procedure ScreenShot(DestBitmap : TBitmap) ;
var
  DC: HDC;
begin
  DC := GetDC (GetDesktopWindow) ;
  try
    DestBitmap.Width := GetDeviceCaps (DC, HORZRES) ;
    DestBitmap.Height := GetDeviceCaps (DC, VERTRES) ;
    BitBlt(DestBitmap.Canvas.Handle,
           0,
           0,
           DestBitmap.Width,
           DestBitmap.Height,
           DC,
           0,
           0,
           SRCCOPY) ;
  finally
    ReleaseDC (GetDesktopWindow, DC) ;
  end;
end;    procedure TForm1.Button1Click(Sender: TObject);
var
  bmp: TBitmap;
begin
  bmp := TBitmap.Create;
  ScreenShot(bmp);
  bmp.SaveToFile('c:\screen.bmp');
  bmp.Free;
end;