类的只读属性形同虚设？

[s11ss]

代码如下，只读属性的值还是被修改了！算是“漏洞”吧？

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure FormCreate(Sender: TObject);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
    Fa: Integer;
  public
    { Public declarations }
    property a: Integer read Fa;
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
  showmessage(IntToStr(a))
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  PInteger(@a)^ := 123;{通过指针方式修改只读属性的值}
end;

[7年]

修改只读属性的方法就是通过指针

[s11ss]

只写属性也是形同虚设。。。

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure FormCreate(Sender: TObject);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
    Fa: Integer;
  public
    { Public declarations }
    property a: Integer write Fa;
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

var
  address: Integer;

procedure TForm1.Button1Click(Sender: TObject);
var
  x: Integer;
begin
  asm{读a的值}
    mov eax, self
    add eax, [address]
    mov eax, [eax]
    mov x,eax
  end;
  showmessage(IntToStr(x))
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  a := 123;
  asm{取a的地址}
  @@:
    mov eax, offset @@
    mov eax,[eax-8]
    mov address,eax
  end;
end;

[蓝色光芒]

property a: Integer read Geta; 用函数就是另一回事了

[s11ss]

[Quote=引用 4 楼 的回复:]
property a: Integer read Geta; 用函数就是另一回事了
[/Quote]同意

[s11ss]

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