using System;

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

public class Program

{

    public static void Main()

    {

        string text = "{ \"pos\": 123 }";

        var res = JsonConvert.DeserializeObject<Sometype>(text);

        Console.WriteLine(res.Pos);

    }

}

​

​

class Sometype

{

    public Number Pos { get; set; }

}

​

class Number

{

    private uint num;

​

    private Number(uint num)

    {

        this.num = num;

    }

    public static implicit operator Number(uint id)

    {

        return new Number(id);

    }

    public static implicit operator Number(long id)

    {

        return new Number((uint)id);

    }

​

    public static implicit operator uint(Number sid)

    {

        return sid.num;

    }

}