public static void Main()
Console.WriteLine(JsonConvert.SerializeObject(new TestData(), new JsonSerializerSettings { TypeNameHandling = TypeNameHandling.Objects }));
var typedJson = @"{""$type"":""Program+TestData, ConsoleApp2"",""TestField"":0}";
var testData = JsonConvert.DeserializeObject(typedJson, new JsonSerializerSettings { TypeNameHandling = TypeNameHandling.Objects });
var json = JsonConvert.SerializeObject(testData);