type  TRec1 = record    i: Integer;    w: Word;  end;  TRec2 = packed record {压缩结构: 牺牲效率, 减小尺寸}    i: Integer;    w: Word;  end;procedure TForm1.Button1Click(Sender: TObject);begin  ShowMessage(IntToStr(SizeOf(TRec1))); {8}  ShowMessage(IntToStr(SizeOf(TRec2))); {6}end;