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 System.Text.Json;

using System.Text.Json.Serialization;

​

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

​

//https://stackoverflow.com/questions/70096362/force-system-text-json-to-deserialize-in-camelcase

​

#nullable enable

​

    public class JsonElementConverter : JsonConverter<JsonElement>

    {

        public override void Write(Utf8JsonWriter writer, JsonElement value, JsonSerializerOptions options)

        {

            switch (value.ValueKind)

            {

                case JsonValueKind.Object:

                    var policy = options.PropertyNamingPolicy;

                    writer.WriteStartObject();

                    foreach (var pair in value.EnumerateObject())

                    {

                        writer.WritePropertyName(policy?.ConvertName(pair.Name) ?? pair.Name);

                        Write(writer, pair.Value, options);

                    }

                    writer.WriteEndObject();

                    break;

                case JsonValueKind.Array:

                    writer.WriteStartArray();

                    foreach (var item in value.EnumerateArray())

                        Write(writer, item, options);

                    writer.WriteEndArray();

                    break;

                default:

                    value.WriteTo(writer);

                    break;

            }

        }

        public override JsonElement Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)

        {

            using var doc = JsonDocument.ParseValue(ref reader);

            return doc.RootElement.Clone();

        }

    }

​

    class TestClass

    {

        public static void Test()

        {

            var jsonString = GetJson();

            using var doc = JsonDocument.Parse(jsonString);

            JsonNamingPolicy policy = JsonNamingPolicy.CamelCase;

            var options = new JsonSerializerOptions

            {

                Converters = { new JsonElementConverter() },

                PropertyNamingPolicy = policy,

                WriteIndented = true // Or false, if you prefer

            };

            Test(doc, options);

​

            var options2 = new JsonSerializerOptions

            {

                Converters = { new JsonElementConverter() },

                WriteIndented = true // Or false, if you prefer

            };

            Test(doc, options2);

            Test(doc, new JsonSerializerOptions { }); // Not indented

        }   

        public static void Test(JsonDocument doc, JsonSerializerOptions options)

        {

            var serialized = JsonSerializer.Serialize(doc.RootElement, options);

            Console.WriteLine(serialized);

        }   

        static string GetJson() => @"

{

    ""Glossary"": [[{

        ""Title"": ""example glossary"",

        ""GlossDiv"": {

            ""Title"": ""S"",

            ""GlossList"": {

""GlossEntry"": {

                    ""ID"": ""SGML"",

                    ""SortAs"": ""SGML"",

                    ""GlossTerm"": ""Standard Generalized Markup Language"",

                    ""Acronym"": ""SGML"",

                    ""Abbrev"": ""ISO 8879:1986"",

                    ""GlossDef"": [[{

                        ""Para"": ""A meta-markup language, used to create markup languages such as DocBook."",

                        ""GlossSeeAlso"": [""GML"", ""XML""]

                    }]],

                    ""GlossSee"": ""markup""

                }

            }

        }

    }]]

}

";

    }

​

    public class Program

    {

        public static void Main()

        {

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

            Console.WriteLine("System.Text.Json version: " + 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 "";

        }

    }

​