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 = @"

            {

                ""users"": [

                    {

                        ""first_name"": ""John"",

                        ""last_name"": ""Smith"",

                        ""vet"": [ ""FOO"", ""VET-1"" ],

                        ""animals"": [ [ ""FOO"", ""ANIMAL-22"" ] ]

                    },

                    {

                        ""first_name"": ""Susan"",

                        ""last_name"": ""Smith"",

                        ""vet"": [ ""FOO"", ""VET-1"" ]

                    }

                ],

                ""BAR"": {

                    ""VET-1"": {

                        ""vet_name"": ""Acme, Inc"",

                        ""vet_id"": 456

                    },

                    ""ANIMAL-22"": {

                        ""animal_name"": ""Fido"",

                        ""species"": ""dog"",

                        ""animal_id"": 789,

                        ""vet"": [ ""FOO"", ""VET-1"" ]

                    }

                }

            }";

        JObject data = JObject.Parse(json);

        Dictionary<string, Vet> vets = data["BAR"]

            .Children<JProperty>()

            .Where(jp => jp.Value["vet_id"] != null)

            .ToDictionary(jp => jp.Name, jp => jp.Value.ToObject<Vet>());

​

        JsonSerializer serializer = new JsonSerializer();

        serializer.Converters.Add(new ReferenceConverter<Vet>(vets));

        Dictionary<string, Animal> animals = data["BAR"]

            .Children<JProperty>()

            .Where(jp => jp.Value["animal_id"] != null)

            .ToDictionary(jp => jp.Name, jp => jp.Value.ToObject<Animal>(serializer));

        serializer.Converters.Add(new ReferenceConverter<Animal>(animals));

        List<User> users = data["users"].ToObject<List<User>>(serializer);

        foreach (User user in users)

        {

            Console.WriteLine("--------------------");

            Console.WriteLine("Name: " + user.FirstName + " " + user.LastName);

            Console.WriteLine("Vet: " + (user.Vet != null ? user.Vet.Name : "(none)"));

            Console.Write("Animals: ");

            if (user.Animals != null && user.Animals.Count > 0)

            {

                Console.WriteLine();

                foreach (Animal a in user.Animals)

                {

                    Console.WriteLine("   Name: " + a.Name);

                    Console.WriteLine("   Species: " + a.Species);

                    Console.WriteLine("   Vet: " + (a.Vet != null ? a.Vet.Name : "(none)"));

                }

            }

            else

            {

                Console.WriteLine("(none)");

            }

        }

    }

}

​

​

public class ReferenceConverter<T> : JsonConverter

{

    private Dictionary<string, T> ReferenceDict { get; set; }

    public ReferenceConverter(Dictionary<string, T> referenceDict)

    {

        ReferenceDict = referenceDict;

    }

    public override bool CanConvert(Type objectType)

    {

        return objectType == typeof(T);

    }

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

    {

        JArray array = JArray.Load(reader);

        if (array.Count == 2 && array[0].Type == JTokenType.String && (string)array[0] == "FOO" && array[1].Type == JTokenType.String)

        {

            string key = (string)array[1];

            T obj;

            if (ReferenceDict.TryGetValue(key, out obj))

                return obj;

            throw new JsonSerializationException("No " + typeof(T).Name + " was found with the key \"" + key + "\".");

        }

        throw new JsonSerializationException("Reference had an invalid format: " + array.ToString());

    }

    public override bool CanWrite

    {

        get { return false; }

    }

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

    {

        throw new NotImplementedException();

    }

}

​

public class User

{

    [JsonProperty("first_name")]

    public string FirstName { get; set; }

    [JsonProperty("last_name")]

    public string LastName { get; set; }

    [JsonProperty("vet")]

    public Vet Vet { get; set; }

    [JsonProperty("animals")]

    public List<Animal> Animals { get; set; }

}

​

public class Vet

{

    [JsonProperty("vet_id")]

    public int Id { get; set; }

    [JsonProperty("vet_name")]

    public string Name { get; set; }

}

​

public class Animal

{

    [JsonProperty("animal_id")]

    public int Id { get; set; }

    [JsonProperty("animal_name")]

    public string Name { get; set; }

    [JsonProperty("vet")]

    public Vet Vet { get; set; }

    [JsonProperty("species")]

    public string Species { get; set; }

}

​