using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.IO;

using System.Reflection;

​

using System.Text.Json;

using System.Text.Json.Serialization;

​

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

​

//https://stackoverflow.com/questions/65956172/problem-with-properties-casing-when-using-system-text-json-jsonserializer-serial

​

    class TestClass

    {

        public static void Test()

        {

            var dictionary = new Dictionary<string, object>()

            {

                {"Key1", 5},

                {"Key2", "aaa"},

                {"Key3", new Dictionary<string, object>(){ {"Key4", 123}}}

            };

            var serialized = JsonSerializer.Serialize(dictionary, new JsonSerializerOptions()

            {

                PropertyNamingPolicy = JsonNamingPolicy.CamelCase,

                DictionaryKeyPolicy = JsonNamingPolicy.CamelCase,

            });         

            Console.WriteLine(serialized);

            Assert.AreEqual(@"{""key1"":5,""key2"":""aaa"",""key3"":{""key4"":123}}", serialized);

        }   

    }

​

    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 null;

        }

    }

​