using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Runtime.Serialization.Formatters;

using System.IO;

using System.Data;

using System.ComponentModel.DataAnnotations;

using System.Globalization;

​

    // https://stackoverflow.com/questions/47923402/deserializing-rest-resource-to-generic-object

    using SimpleJson;

    using RestSharp;

​

    public abstract class PostalAddressOccupancy

    {

        public DateTime EffectiveDate { get; set; }

        public DateTime EndDate { get; set; }

        public string EntityType { get; set; }

        public string Href { get; set; }

        public string Id { get; set; }

        public bool IsCorrespondenceAddress { get; set; }

        public PostalAddress PostalAddress { get; set; }

        public string PostalAddressType { get; set; }

​

        public abstract object GetOccupant();

    }

​

    public class PostalAddressOccupancy<T> : PostalAddressOccupancy

    {

        public T Occupant { get; set; }

​

        public override object GetOccupant()

        {

            return Occupant;

        }

    }

​

    public class PostalAddress

    {

        // Or whatever.  Type was not included in the question.

        public string Address { get; set; }

    }

​

    public class Student

    {

        public string Name { get; set; }

        public string StudentId { get; set; }

    }

​

    public class Staff

    {

        public string Name { get; set; }

        public string StaffId { get; set; }

    }

​

    public static class PostalAddressOccupancyExtensions

    {

        public static PostalAddressOccupancy DeserializePostalAddressOccupancy(this RestSharp.IRestResponse response)

        {

            var addressObj = (JsonObject)SimpleJson.SimpleJson.DeserializeObject(response.Content);

            var type = PostalAddressOccupancyExtensions.InferPostalAddressOccupancyType(addressObj);

            return (PostalAddressOccupancy)SimpleJson.SimpleJson.DeserializeObject(response.Content, type);

        }

​

        static Type InferPostalAddressOccupancyType(JsonObject root)

        {

            var occupantObj = root["Occupant"];

            if (occupantObj is JsonObject)

            {

                var occupant = (JsonObject)occupantObj;

                // Add logic to recognize other cases as required.

                if (occupant.ContainsKey("StudentId"))

                {

                    return typeof(PostalAddressOccupancy<Student>);

                }

                else if (occupant.ContainsKey("StaffId"))

                {

                    return typeof(PostalAddressOccupancy<Staff>);

                }

            }

            // Or throw an exception, if you prefer.

            return typeof(PostalAddressOccupancy<>).MakeGenericType(new[] { occupantObj.GetType() });

        }

    }

​

    class TestClass

    {

        public static void Test()

        {

            Console.WriteLine("RestSharp version: " + typeof(RestResponse).Assembly.FullName);

            Console.WriteLine();

​

            Test(new Staff { Name = "my name", StaffId = "222" });

            Test(new Student { Name = "some kid", StudentId = "-121" });

        }

​

        static void Test<T>(T occupant)

        {

            var address = new PostalAddressOccupancy<T>

            {

                EffectiveDate = new DateTime(2016, 2, 2),

                EndDate = new DateTime(2020, 2, 2),

                EntityType = "foo",

                Href = "http://foo",

                Id = "1010101",

                IsCorrespondenceAddress = true,

                PostalAddress = new PostalAddress { Address = "po box here" },

                PostalAddressType = "po box",

                Occupant = occupant,

            };

​

            var json = Newtonsoft.Json.JsonConvert.SerializeObject(address, Newtonsoft.Json.Formatting.Indented);

            Console.WriteLine("\nInput JSON: ");

            Console.WriteLine(json);

​

            RestSharp.RestResponse response = new RestSharp.RestResponse();

            response.Content = json;

            response.ContentType = "application/json";

​

            var address2 = response.DeserializePostalAddressOccupancy();

​

            Assert.IsTrue(address.GetOccupant().GetType() == address2.GetOccupant().GetType());

​

            var json2 = Newtonsoft.Json.JsonConvert.SerializeObject(address2, Newtonsoft.Json.Formatting.Indented);

​

            Console.WriteLine("\nDeserialized and re-serialized {0}:", address);

            Console.WriteLine(json2);

        }

    }

​

    public class Program

    {

        public static void Main()

        {

            Console.WriteLine("Environment version: " + Environment.Version);

            //Console.WriteLine("Json.NET version: " + typeof(Newtonsoft.Json.JsonSerializer).Assembly.FullName);

            Console.WriteLine("RestSharp version: " + typeof(RestResponse).Assembly.FullName);

            Console.WriteLine();

​

            try

            {

                TestClass.Test();

            }

            catch (Exception ex)

            {

                Console.WriteLine("Failed with unhandled exception: ");

                Console.WriteLine(ex);

                throw;

            }

        }

    }

​

    public class AssertionFailedException : System.Exception

    {

        public AssertionFailedException() : base() { }

​

        public AssertionFailedException(string s) : base(s) { }

    }

​

    public static class Assert

    {

        public static void IsTrue(bool value)

        {

            IsTrue(value, "failed");

        }

​

        public static void IsTrue(bool value, string message)

        {

            if (value == false)

                throw new AssertionFailedException(message ?? "failed");

        }

    }

​