using System;

using System.Collections.Generic;

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

public class Program

{

    public static void Main()

    {

        string text = "{ \"Id\": 321, \"Ids\": [{ \"Id\": 123 }] }";

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

        Console.WriteLine(res.Id.Id);

        Console.WriteLine(res.Ids[0].Id);

    }

}

​

​

class Sometype

{

    public MobId Id { get; set; }

    public List<MobId> Ids { get; set; }

}

​

​

public struct MobId {

    public readonly int Id;

    public MobId(int id) {

        Id = id;

    }

    public static implicit operator int(MobId mobId) {

        return mobId.Id;

    }

    public static implicit operator MobId(long id) {

        return new MobId((int)id);

    }

    public bool Equals(MobId other) {

        return Id == other.Id;

    }

    public override bool Equals(object obj) {

        if (ReferenceEquals(null, obj)) return false;

        return obj is MobId && Equals((MobId) obj);

    }

    public override int GetHashCode() {

        return Id.GetHashCode();

    }

    public static bool operator ==(MobId left, MobId right) {

        return left.Equals(right);

    }

    public static bool operator !=(MobId left, MobId right) {

        return !left.Equals(right);

    }

    public override string ToString() {

        return string.Format("MobId#{0}", Id);

    }

}