unit UnitMyClass;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
TMyClass   =   Class
private    
    FField1:   integer;    
    FField2:   string;

    FField3:   boolean;  
    function   GetField3:   boolean;    
    procedure   SetField3(AField:   boolean);    
public    
    property   Field1:   integer   read   FField1   write   FField1;
published
    //property   Field1:   integer   read   FField1   write   FField1;
    property   Field2:   string   read   FField2;
    property   Field3:   boolean   read   GetField3   write   SetField3;    
end;

procedure WriteConstObj(const obj:TMyClass);forward;

implementation

function   TMyClass.GetField3:   boolean;    
begin    
    //注意这里用FField3而不是Field3.    
    result   :=   FField3;    
end;    
  
procedure   TMyClass.SetField3(AField:   boolean);    
begin    
    //注意这里用FField3而不是用Field3，因为Field3是专门供外部使用的。    
    FField3   :=   AField;    
end;

procedure WriteConstObj(const obj:TMyClass);
begin
  obj.FField1:=obj.FField1+1;
end;


end.