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 System.Collections.ObjectModel;

​

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/67218063/how-to-apply-itemconvertertype-when-deserializing-a-multidimensional-array

​

    public class JaggedArrayItemConverterDecorator : JsonConverter

    {

        readonly JsonConverter itemConverter;

​

        public JaggedArrayItemConverterDecorator(Type type) => 

            itemConverter = (JsonConverter)Activator.CreateInstance(type ?? throw new ArgumentNullException());

​

        public override bool CanConvert(Type objectType) => objectType.IsJaggedRankOneArray(out var itemType) && itemConverter.CanConvert(itemType);

​

        public override bool CanRead => itemConverter.CanRead;

        public override bool CanWrite => itemConverter.CanWrite;

​

        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)

        {

            if (reader.MoveToContentAndAssert().TokenType == JsonToken.Null)

                return null;

            if (reader.TokenType != JsonToken.StartArray)

                throw new JsonSerializationException(string.Format("Unexpected token {0}, expected {1}", reader.TokenType, JsonToken.StartArray));

            var itemType = objectType.GetElementType();

            IList list = (IList)serializer.ContractResolver.ResolveContract(typeof(List<>).MakeGenericType(itemType)).DefaultCreator();

            while (reader.ReadToContentAndAssert().TokenType != JsonToken.EndArray)

            {

                if (itemType.IsArray)

                    list.Add(ReadJson(reader, itemType, null, serializer));

                else

                    list.Add(itemConverter.ReadJson(reader, itemType, null, serializer));

            }

            var array = Array.CreateInstance(itemType, list.Count);

            list.CopyTo(array, 0);

            return array;

        }

​

        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)

        {

            var itemType = value.GetType().GetElementType();

            writer.WriteStartArray();

            foreach (var item in (IList)value)

            {

                if (item == null)

                    writer.WriteNull();

                else if (itemType.IsArray)

                    WriteJson(writer, item, serializer);

                else

                    itemConverter.WriteJson(writer, item, serializer);

            }

            writer.WriteEndArray();

        }

    }

​

    public static partial class JsonExtensions

    {

        public static JsonReader ReadToContentAndAssert(this JsonReader reader) =>

            reader.ReadAndAssert().MoveToContentAndAssert();

​

        public static JsonReader MoveToContentAndAssert(this JsonReader reader)

        {

            if (reader == null)

                throw new ArgumentNullException();

            if (reader.TokenType == JsonToken.None)       // Skip past beginning of stream.

                reader.ReadAndAssert();

            while (reader.TokenType == JsonToken.Comment) // Skip past comments.

                reader.ReadAndAssert();

            return reader;

        }

​

        public static JsonReader ReadAndAssert(this JsonReader reader)

        {

            if (reader == null)

                throw new ArgumentNullException();

            if (!reader.Read())

                throw new JsonReaderException("Unexpected end of JSON stream.");

            return reader;

        }

    }

​

    public static class TypeExtensions

    {

        public static bool IsJaggedRankOneArray(this Type type, out Type innermostItemType)

        {

            innermostItemType = null;

            var currentType = type ?? throw new ArgumentNullException(nameof(type));

            while (currentType.IsArray)

            {

                if (currentType.GetArrayRank() != 1)

                    return false;

                currentType = currentType.GetElementType();

            }

            if (currentType != type)

            {

                innermostItemType = currentType;

                return true;

            }

            return false;

        }

    }

​

    public class InternedString : JsonConverter<string>

    {

        public const string prefix = "prefix: ";

        public override void WriteJson(JsonWriter writer, string value, JsonSerializer serializer) => writer.WriteValue(prefix + value);

​

        public override string ReadJson(JsonReader reader, Type objectType, string existingValue, bool hasExistingValue, JsonSerializer serializer)

        {

            if (reader.MoveToContentAndAssert().TokenType == JsonToken.Null)

                return null;

            else if (reader.TokenType == JsonToken.String)

            {

                var s = (string)reader.Value;

                if (s.StartsWith(prefix))

                    s = s.Substring(prefix.Length, s.Length - prefix.Length);

                return s;

            }

            else 

                throw new JsonSerializationException();

        }       

    }

​

    public class Model

    {

        [JsonProperty(ItemConverterType=typeof(InternedString))] // For 1d arrays you can use either ItemConverterType=typeof(InternedString) or JaggedArrayItemConverterDecorator

        public string[] prizeTypes { get; set; }

​

        [JsonConverter(typeof(JaggedArrayItemConverterDecorator), typeof(InternedString))]

        public string[] prizeTypesByRoomType { get; set; }

​

        [JsonConverter(typeof(JaggedArrayItemConverterDecorator), typeof(InternedString))]

        public string[][] prizeTypesByRoomType2d { get; set; }

​

        [JsonConverter(typeof(JaggedArrayItemConverterDecorator), typeof(InternedString))]

        public string[][][] prizeTypesByRoomType3d { get; set; }

​

        [JsonConverter(typeof(JaggedArrayItemConverterDecorator), typeof(InternedString))]

        public string[][][][] prizeTypesByRoomType4d { get; set; }

        [JsonProperty(ItemConverterType=typeof(InternedString))] // ItemConverterType works for multidimensional arrays

        [System.Text.Json.Serialization.JsonIgnoreAttribute]

        public string[,] prizeTypesMultidimensional { get; set; }

    }

​

    class TestClass

    {

        public static void Test()

        {

            var model = new Model

            {

                prizeTypes = new [] { "a", "b" },

                prizeTypesByRoomType = new [] { "a", "b", "c", "d", null },

                prizeTypesByRoomType2d = new [] { new [] { "a", "b" }, new [] { "a", "b" } },

                prizeTypesByRoomType3d = new [] { new [] { new [] { "a", "b" }, new [] { "a", "b" } }, new [] { new [] { "a", "b" }, new [] { "a", "b" } } },

                prizeTypesByRoomType4d = new [] { new [] { new [] { new [] { "a", "b" }, new [] { "a", "b" } }, new [] { new [] { "a", "b" }, new [] { "a", "b" } } }, new [] { new [] { new [] { "a", "b" }, new [] { "a", "b" } }, new [] { new [] { "a", "b" }, new [] { "a", "b" } } }, null },

​

                prizeTypesMultidimensional = new [,] { {"a", "b"}, {"c", "d" } },

            };

            var json1 = JsonConvert.SerializeObject(model, Formatting.Indented);

            Assert.IsTrue(!json1.Contains("\"a\""));

            Assert.IsTrue(json1.Contains("\"prefix: a\""));

            var defaultJson1 = System.Text.Json.JsonSerializer.Serialize(model);

            Console.WriteLine(json1);

            var model2 = JsonConvert.DeserializeObject<Model>(json1);

            var json2 = JsonConvert.SerializeObject(model2, Formatting.Indented);

​

            var defaultJson2 = System.Text.Json.JsonSerializer.Serialize(model2);

​

            Assert.AreEqual(defaultJson1, defaultJson2);

            Assert.AreEqual(json1, json2);

            Assert.AreEqual(model.prizeTypesMultidimensional.GetLength(0), model.prizeTypesMultidimensional.GetLength(1));

            Assert.IsTrue(model.prizeTypesMultidimensional.Cast<string>().SequenceEqual(model2.prizeTypesMultidimensional.Cast<string>()));

        }

    }

​

    public class Program

    {

        public static void Main()

        {

            Console.WriteLine("Environment version: {0} ({1})", System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription , GetNetCoreVersion());

            Console.WriteLine("{0} version: {1}", typeof(JsonSerializer).Assembly.GetName().Name,  typeof(JsonSerializer).Assembly.FullName);

            Console.WriteLine();

​

            try

            {

                TestClass.Test();

            }

            catch (Exception ex)

            {

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

                Console.WriteLine(ex);

                throw;

            }

        }

        public static string GetNetCoreVersion()

        {

            //https://techblog.dorogin.com/how-to-detect-net-core-version-in-runtime-ecd65ad695be

            //

            var assembly = typeof(System.Runtime.GCSettings).GetTypeInfo().Assembly;

            var assemblyPath = assembly.Location.Split(new[] { '/', '\\' }, StringSplitOptions.RemoveEmptyEntries);

            int netCoreAppIndex = Array.IndexOf(assemblyPath, "Microsoft.NETCore.App");

            if (netCoreAppIndex > 0 && netCoreAppIndex < assemblyPath.Length - 2)

                return assemblyPath[netCoreAppIndex + 1];

            return null;

        }

    }

​