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;

using System.Reflection;

​

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

using Newtonsoft.Json.Converters;

using Newtonsoft.Json.Serialization;    

​

using NUnit.Framework; // Throws NUnit.Framework.AssertionException

​

//https://stackoverflow.com/questions/57500522/trying-serialize-to-json-only-the-base-class

​

    public class UpcastingContractResolver<TDerived, TBase> : DefaultContractResolver where TDerived: TBase

    {

        // Copied from this answer https://stackoverflow.com/a/56468144/3744182

        // to https://stackoverflow.com/questions/56467203/how-to-exclude-properties-from-jsonconvert-populateobject-that-dont-exist-in-so/

        readonly HashSet<string> baseProperties = ((JsonObjectContract)JsonSerializer.Create().ContractResolver.ResolveContract(typeof(TBase)))

            .Properties.Select(p => p.UnderlyingName)

            .ToHashSet();

​

        protected override IList<JsonProperty> CreateProperties(Type type, MemberSerialization memberSerialization)

        {

            var properties = base.CreateProperties(type, memberSerialization);

            if (type == typeof(TDerived) || type.IsSubclassOf(typeof(TDerived)))

            {

                foreach (var property in properties)

                {

                    if (!baseProperties.Contains(property.UnderlyingName))

                        property.Ignored = true;

                }

            }

            return properties;

        }

    }

​

    [JsonObject(MemberSerialization.OptIn)]

    public class RecipeShort

    {

        [JsonProperty]

        public string Id { get; set; }

​

        [JsonProperty]

        public string Title { get; set; }

    }

​

    [JsonObject(MemberSerialization.OptIn)]

    public class Recipe : RecipeShort

    {

        [JsonProperty]

        private List<Ingredient> ingredients = new List<Ingredient>();

​

        [JsonProperty]

        public string Method { get; set; }

    }

    public class Ingredient

    {

    }

​

    class TestClass

    {

        public static void Test()

        {

            var res = new Recipe

            {

                Id = "123",

                Title = "Text",

                Method ="Text",

            };          

​

            string str1 = Newtonsoft.Json.JsonConvert.SerializeObject(res);

            Console.WriteLine("\nDefault serialization of {0}", res);

            Console.WriteLine(str1);

            var settings = new JsonSerializerSettings

            {

                ContractResolver = new UpcastingContractResolver<Recipe, RecipeShort>(),

            };

            var str2 = Newtonsoft.Json.JsonConvert.SerializeObject(res, settings);

            Console.WriteLine("\nSerialization of {0} using {1}", res, settings.ContractResolver);

            Console.WriteLine(str2);

        }   

        static string GetJson()

        {

            var json = @"

";

            return json;

        }

    }

​

    public class Program

    {

        public static void Main()

        {

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

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

            Console.WriteLine();

​

            try

            {

                TestClass.Test();

            }

            catch (Exception ex)

            {

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

                Console.WriteLine(ex);

                throw;

            }

        }

    }

​