using System;

using Newtonsoft.Json;

public class Program

{

    public static void Main()

    {

        var json = "{ \"userID\": \"FooName\", \"userType\": \"FooType\" }";

        var fooUser = JsonConvert.DeserializeObject<FooUser>(json);

        Console.WriteLine(fooUser.UserID);

        Console.WriteLine(fooUser.UserType);

    }

}

​

public class FooUser 

{

    public string UserID { get; set; }

    public string UserType { get; private set; }

    public FooUser()

    {

        this.UserType = "FooType";

    }

}