using System;

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

public class Program

{

    public static void Main()

    {

        string json = @"

            {

              ""type"": ""bank"",

              ""bank"": ""Some value"",

            }";

        DeserializeDumpAndReserialize(json);

        json = @"

            {

              ""type"": ""card"",

              ""card"": ""Some other value""

            }";

        DeserializeDumpAndReserialize(json);

    }

    public static void DeserializeDumpAndReserialize(string json)

    {

        MyRequest req = JsonConvert.DeserializeObject<MyRequest>(json);

        Console.WriteLine("Type: " + req.Type);

        Console.WriteLine("Source: " + req.Source);

        Console.WriteLine(JsonConvert.SerializeObject(req));

        Console.WriteLine();

    }

}

​

public class MyRequestConverter : JsonConverter

{

    public override bool CanConvert(Type objectType)

    {

        return objectType == typeof(MyRequest);

    }

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

    {

        JObject jo = JObject.Load(reader);

        string type = (string)jo["type"];

        MyRequest req = new MyRequest

        {

            Type = type,

            Source = (string)jo[type ?? ""]

        };

        return req;

    }

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

    {

        MyRequest req = (MyRequest)value;

        JObject jo = new JObject(

            new JProperty("type", req.Type),

            new JProperty(req.Type, req.Source));

        jo.WriteTo(writer);

    }

}

​

​

[JsonConverter(typeof(MyRequestConverter))]

public class MyRequest

{

    public string Type { get; set; }

    public string Source { get; set; }

}

​