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.RegularExpressions;

​

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/66892444/cannot-set-a-custom-contract-resolver-in-web-api-configuration?noredirect=1#comment118245597_66892444

​

    public class TestModel

    {

        public decimal CODE_IDENTIFICATION { get; set; }

​

        public string DEFAULT_DESCRIPTION { get; set; }

    }

​

    public class CustomContractResolver : DefaultContractResolver

    {

        readonly NamingStrategy baseNamingStrategy = new CamelCaseNamingStrategy();

        protected override string ResolvePropertyName(string propertyName)

        {

            var regex = new Regex(@"([_])(\w)");

​

            if (regex.IsMatch(propertyName))

            {

                var result = regex.Replace(propertyName.ToLower(), (match) => { return match.Groups[2].Value.ToUpper(); });

                return result;

            }

            else

                return baseNamingStrategy.GetPropertyName(propertyName, false);

        }

    }

​

    class TestClass

    {

        public static void Test()

        {

            var test = new TestModel { CODE_IDENTIFICATION = 1, DEFAULT_DESCRIPTION = "TEST DAT THING" };

            var settings = new JsonSerializerSettings

            {

                ContractResolver = new CustomContractResolver(),

            };

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

            Console.WriteLine(json);

        }   

    }

​

    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;

        }

    }

​