TTMSFNCObjectHelper = class helper for TObject
    function ToJSON(AExcludedProperties: TTMSFNCObjectExcludePropertyListArray): string; overload;
    function ToJSON: string; overload;
    procedure FromJSON(const Value: string);
    property JSON: string read ToJSON write FromJSON;
    procedure Log;
    {$IFNDEF WEBLIB}
    procedure SaveToJSONFile(const AFileName: string);
    procedure LoadFromJSONFile(const AFileName: string);
    {$ENDIF}
    procedure SaveToJSONStream(const AStream: TStream);
    procedure LoadFromJSONStream(const AStream: TStream);
  end;

  TTestClass = class(TPersistent)
  private
    FB: string;
    FC: Double;
    FA: Boolean;
  published
    property A: Boolean read FA;
    property B: string read FB write FB;
    property C: Double read FC write FC;
  end;

var
  t: TTestClass;
begin
  t := TTestClass.Create;
  t.FA := True;
  t.FB := 'Hello World!';
  t.FC := 123.456;

  t.JSON.Log;
end;

Debug Output: {"$type":"TTestClass","A":true,"B":"Hello World!","C":123.456} Process Project1.exe (6968)