using System;

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

public class Program

{

    public static void Main()

    {

        string json = @"

            {

              ""ticket_id"": ""A1234"",

              ""sellPrice"": {

                ""currency"": ""EUR"",

                ""amount"": 60.25

              }

            }";

​

        DeserializeAndDump(json);

​

        json = @"

            {

              ""ticket_id"": ""B9876"",

              ""sellPrice"": 75.95

            }";

​

        DeserializeAndDump(json);

    }

​

    private static void DeserializeAndDump(string json)

    {

        Ticket ticket = JsonConvert.DeserializeObject<Ticket>(json);

        Console.WriteLine("id: " + ticket.Ticket_Id);

        Console.WriteLine("currency: " + ticket.SellPrice.Currency);

        Console.WriteLine("amount: " + ticket.SellPrice.Amount);

        Console.WriteLine();

    }

}

​

public class Ticket

{

    public string Ticket_Id { get; set; }

    //... other fields

    public SellPrice SellPrice { get; set; }

}

​

[JsonConverter(typeof(SellPriceConverter))]

public class SellPrice

{

    public string Currency { get; set; }

    public double Amount { get; set; }

}

​

public class SellPriceConverter : JsonConverter

{

    public override bool CanConvert(Type objectType)

    {

        return objectType == typeof(SellPrice);

    }

​

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

    {

        JToken token = JToken.Load(reader);

        SellPrice sellPrice = new SellPrice();

        if (token.Type == JTokenType.Object)

        {

            serializer.Populate(token.CreateReader(), sellPrice);

        }

        else if (token.Type == JTokenType.Float)

        {

            sellPrice.Amount = (double)token;

            // if there is a default currency, set it here, e.g.:

            // sellPrice.Currency = "USD";

        }

        else

        {

            throw new JsonException("Unexpected token type for SellPrice: " + token.Type.ToString());

        }

        return sellPrice;

    }

​

    public override bool CanWrite

    {

        get { return false; }

    }

​

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

    {

        throw new NotImplementedException();

    }

}

​