using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.IO;

using System.Data;

using System.Globalization;

using System.Reflection;

​

using System.Drawing;

​

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/72352865/serialize-list-of-objects-with-string-properties-to-json-array-of-objects

​

    public class RootObject

    {

        public Property Properties { get; set; }

    }

​

    public class Property

    {

        public string MyFirstProp { get; set; }

        public string MySecondProp {get; set; }

    }

​

    public class ObjectAsObjectArrayConverter<TObject> : JsonConverter<TObject>

    {

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

        {

            var contract = (serializer.ContractResolver.ResolveContract(value.GetType()) as JsonObjectContract) ?? throw new ArgumentException("Wrong contract type");

            writer.WriteStartArray();

            foreach (var property in contract.Properties.Where(p => ShouldSerialize(p, value)))

            {

                var propertyValue = property.ValueProvider.GetValue(value);

                if (propertyValue == null && (serializer.NullValueHandling == NullValueHandling.Ignore || property.NullValueHandling == NullValueHandling.Ignore))

                    continue;

                writer.WriteStartObject();

                writer.WritePropertyName(property.PropertyName);

                if (propertyValue == null)

                    writer.WriteNull();

                else if (property.Converter != null && property.Converter.CanWrite)

                    property.Converter.WriteJson(writer, propertyValue, serializer);

                else

                    serializer.Serialize(writer, propertyValue);

                writer.WriteEndObject();

            }

            writer.WriteEndArray();

        }

​

        protected virtual bool ShouldSerialize(JsonProperty property, object value) =>

            property.Readable && !property.Ignored && (property.ShouldSerialize == null || property.ShouldSerialize(value));

​

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

        {

            if (existingValue == null)

                existingValue = (TObject)serializer.ContractResolver.ResolveContract(objectType).DefaultCreator();

​

            switch (reader.MoveToContentAndAssert().TokenType)

            {

                case JsonToken.Null:

                    return (TObject)(object)null;

                case JsonToken.StartArray:

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

                    {

                        switch (reader.TokenType)

                        {

                            case JsonToken.StartObject:

                                serializer.Populate(reader, existingValue);

                                break;

                            default:

                                throw new JsonSerializationException("Unexpected token type " + reader.TokenType.ToString());

                        }

                    }

                    break;

​

                case JsonToken.StartObject:

                    serializer.Populate(reader, existingValue);

                    break;

​

                default:

                    throw new JsonSerializationException("Unexpected token type " + reader.TokenType.ToString());

            }

            return existingValue;

        }

    }

    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;

        }

    }

​

    class TestClass

    {

        public static void Test()

        {

            var myClass = new RootObject

            {

                Properties = new ()

                {

                    MyFirstProp = "Hello",

                    MySecondProp = "World",

                },

            };

​

            var settings = new JsonSerializerSettings

            {

                Converters = { new ObjectAsObjectArrayConverter<Property>() },

            };

            var json = JsonConvert.SerializeObject(myClass, Formatting.Indented, settings);

            Console.WriteLine(json);

            var myClass2 = JsonConvert.DeserializeObject<RootObject>(json, settings);

            Assert.AreEqual(myClass?.Properties?.MyFirstProp, myClass2?.Properties?.MyFirstProp);

            Assert.AreEqual(myClass?.Properties?.MySecondProp, myClass2?.Properties?.MySecondProp);

        }   

    }

​

    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;

        }

    }

​