using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.IO;

using System.Threading;

using System.Collections.ObjectModel;

using System.Reflection;

using System.ComponentModel;

using System.Globalization;

using System.Collections.Specialized;

​

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

using Newtonsoft.Json.Converters;

using Newtonsoft.Json.Serialization;

#if false

    // https://stackoverflow.com/questions/40499272/json-desrialization-of-derived-types/40514862#40514862

#endif

​

​

class Attribute1

{

}

​

class Attribute2 : Attribute1

{

}

class class1

{

    public Attribute1 attr1;

}

​

class class2  : class1

{

    public Attribute2 attr2;

}

​

​

public class Program

{

    public static void Main()

    {

        var serializerSettings = new JsonSerializerSettings()

        {

            TypeNameAssemblyFormat = System.Runtime.Serialization.Formatters.FormatterAssemblyStyle.Full, // Required on dotnetfiddle (for security reasons?)

            TypeNameHandling = TypeNameHandling.Objects,

            Formatting = Formatting.Indented,

        };

        class2 a = new class2

        {

            attr1 = new Attribute2(),

            attr2 = new Attribute2(),

        };

        string serializedClass2 = JsonConvert.SerializeObject(a, serializerSettings);

        Console.WriteLine("Json: ");

        Console.WriteLine(serializedClass2);

        Console.WriteLine("");

        var am =  JsonConvert.DeserializeObject<class2>(serializedClass2);

        Console.WriteLine("Deserialized class2 without TypeNameHandling.Objects: ");

        Console.WriteLine("attr1.GetType() = {0}, attr2.GetType() = {1}", am.attr1.GetType(), am.attr2.GetType());

        Console.WriteLine("");

        var am2 =  JsonConvert.DeserializeObject<class2>(serializedClass2, serializerSettings);

​

        Console.WriteLine("Deserialized class2 WITH TypeNameHandling.Objects: ");

        Console.WriteLine("attr1.GetType() = {0}, attr2.GetType() = {1}", am2.attr1.GetType(), am2.attr2.GetType());

        Console.WriteLine("");

    }

}