保存类对象数据

Question

unit Znxj;interface
uses
SysUtils,Classes;
type
   TRecord =  class
         content:string;
         XGlink:Tstrings;
     public
       procedure AddFile(FileName:string);
       procedure Addlinks(linkname:Tstrings);
       constructor create();overload;
       destructor destroy;override;
     end;
   Frecord= file of Trecord;
    DRecord= class
       Filedir:string;
       znFile:Frecord;
       currec:longint;
       pos:longint;
         num:integer;
      public      
      procedure readrecordtofile(recfile:TRecord);
      procedure readrecordout(pos1:longint;Recfile:Trecord);
      constructor create(FileDir:string);overload;
      destructor destroy;override;
    end;
implementation
{ DRecord }
constructor DRecord.create(FileDir: string);
begin
pos:=0;
Filedir:=FileDir;
currec:=0;
if fileexists(FileDir)then
begin
assignfile(znFile,FileDir);
reset(znfile);
end
else
begin
assignfile(znFile,FileDir);
rewrite(znfile);
end;
end;
destructor DRecord.destroy;
begin
  inherited;
end;
{ TDGRecord }
procedure DRecord.readrecordout(pos1:longint;Recfile:Trecord);
begin
pos:=pos1;
seek(znfile,pos);
read(znfile,Recfile);
end;
procedure DRecord.readrecordtofile(recfile: TRecord);
begin
seek(znfile,currec);
write(znfile,RecFile);
currec:=currec+1;
end;
{ TRecord }
procedure TRecord.AddFile(FileName: string);
begin
 content:=FileName;
end;
procedure TRecord.Addlinks(linkname: tstrings);
begin
XGlink:=linkname;
end;
constructor TRecord.create;
begin
end;
destructor TRecord.destroy;
begin
   inherited;
end;
end.
以上是Frecord类保存TRecord类的对象数据。可是实现不了。