anchor.diff:    PDRawValue = ^TDRawValue;
   
     /// һֵ
  +  ///  ޸ʱҪҪ޸RawCopyFrom
     TDRawInnerValue = record
       case Integer of
         0:
  
positive.code:     begin
        raise Exception.CreateFmt('%s:%s:%s', [e.ClassName, lvDebug, e.Message]);
      end;
    end;
  end;
  
  
negative.code: 
      procedure SetAsString(const Value: String);
    public
      procedure CloneFrom(pvSource: TDValueItem; pvIgnoreValueTypes: TDValueDataTypes
          = [vdtInterface, vdtObject, vdtPtr]);
  
      /// <summary>
      ///   Ϊ鷽ʽͬʱС
      ///    ֮ǰ鷽ʽᱻ
  