这个代码帮忙看!

Question

Function Cjt_LoadFromFile(SourceFile,TargetFile :string):Boolean;
var
  Source:TFileStream;
  Target:TMemoryStream;
  MyFileSize:integer;
begin
  try
    Target:=TMemoryStream.Create;
    Source:=TFileStream.Create(SourceFile,fmOpenRead or fmShareDenyNone);
    try
      Source.Seek(-sizeof(MyFileSize), soFromEnd);
      Source.ReadBuffer(MyFileSize, sizeof(MyFileSize)); //读出资源大小
      Source.Seek(-MyFileSize,soFromEnd);//定位到资源位置
      Target.CopyFrom(Source,MyFileSize - sizeof(MyFileSize));//取出资源
      Target.SaveToFile(TargetFile);//存放到文件
    finally
      Target.Free;
      Source.Free;
    end;
  except
    Result:=false;
    Exit;
  end;
  Result:=true;
end;Target.CopyFrom(Source,MyFileSize - sizeof(MyFileSize));//取出资源
读写错误！！！！  不知道这句怎么改！ 

Answer 1

Source.ReadBuffer(@MyFileSize, sizeof(MyFileSize)); //读出资源大小

Answer 2

Source.Seek(-Sizeof(MyFileSize) -MyFileSize,soFromEnd);//定位到资源位置

Answer 3

看不懂啊！他就报这个有错啊！
Target.CopyFrom(Source,MyFileSize - sizeof(MyFileSize));//取出资源