function CreateScreenshot: TBitmap;
var
  dw: HWND;
  dc: HDC;
begin
  Result := TBitmap.Create;
  Result.Width := Screen.Width;
  Result.Height := Screen.Height;
  dw := GetDesktopWindow;
  dc := GetDC(dw);
  BitBlt(Result.Canvas.Handle, 0, 0, Result.Width, Result.Height,
    dc, 0, 0, SRCCOPY);
  ReleaseDC(dw, dc);
end;