using System;

using System.Collections.Generic;

using System.Linq;

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

public class Program

{

    public static void Main()

    {

        string json = @"

            {

              ""Author"": ""me"",

              ""Version"": ""1.0.0"",

              ""data.Type1"": {

                ""Children"": [

                  {

                    ""data.Type1"": {

                      ""Children"": [

                        {

                          ""data.Type2"": {

                            ""name"": ""John"",

                            ""surname"": ""Doe""

                          }

                        }

                      ]

                    }

                  },

                  {

                    ""data.Type3"": {

                      ""dob"": ""1990-01-01""

                    }

                  }

                ]

              }

            }";

        Root root = JsonConvert.DeserializeObject<Root>(json, new CustomConverter());

        JsonSerializerSettings settings = new JsonSerializerSettings

        {

            DateFormatString = "yyyy-MM-dd",

            Formatting = Formatting.Indented

        };

        Console.WriteLine(JsonConvert.SerializeObject(root, settings));

    }

}

​

class CustomConverter : JsonConverter

{

    public override bool CanConvert(Type objectType)

    {

        return (objectType == typeof(Root));

    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)

    {

        JObject obj = JObject.Load(reader);

        Root root = new Root();

        root.Author = (string)obj["Author"];

        root.Version = (string)obj["Version"];

        root.Children = ((Type1)DeserializeTypeX(obj, serializer)).Children;

        return root;

    }

    private object DeserializeTypeX(JObject obj, JsonSerializer serializer)

    {

        JProperty prop = obj.Properties().Where(p => p.Name.StartsWith("data.")).First();

        JObject child = (JObject)prop.Value;

        if (prop.Name == "data.Type1")

        {

            List<object> children = new List<object>();

            foreach (JObject jo in child["Children"].Children<JObject>())

            {

                children.Add(DeserializeTypeX(jo, serializer));

            }

            return new Type1 { Children = children };

        }

        else if (prop.Name == "data.Type2")

        {

            return child.ToObject<Type2>(serializer);

        }

        else if (prop.Name == "data.Type3")

        {

            return child.ToObject<Type3>(serializer);

        }

        throw new JsonSerializationException("Unrecognized type: " + prop.Name);

    }

    public override bool CanWrite

    {

        get { return false; }

    }

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)

    {

        throw new NotImplementedException();

    }

}

​

class Root

{

    public string Author { get; set; }

    public string Version { get; set; }

    public ICollection<object> Children { get; set; }

}

​

class Type1

{

    public ICollection<object> Children { get; set; }

}

​

class Type2

{

    public string Name { get; set; }

    public string Surname { get; set; }

}

​

class Type3

{

    public DateTime DoB { get; set; }

}

​