[Decoding]

Код:

procedure GetWindowsScreen( PathToSave: string );
begin
   with TBitmap.Create do
   begin
      Width := Screen.Width;
      Height := Screen.Height;
      BitBlt( Canvas.Handle, 0, 0, Width, Height, GetDC( GetDesktopWindow ), 0, 0, SRCCOPY );
      SaveToFile( PathToSave );
      Free;
   end;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
   GetWindowsScreen( 'C:\Screen.bmp' );
end;