using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Net;

using System.Xml;

using System.IO;

​

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

using Newtonsoft.Json.Converters;

using Newtonsoft.Json.Serialization;

​

// https://stackoverflow.com/questions/43742037/json-net-using-jsonconvert-serializeobject-adds-a-comment-to-output

​

    class TestClass

    {

        public void Test(string xmlString)

        {

            var xml = new XmlDocument();

            xml.LoadXml(xmlString);

            var json = GetJson(xml);

            Console.WriteLine("Original XML: ");

            Console.WriteLine(GetXml());

            Console.WriteLine();

            Console.WriteLine("Resulting JSON: ");

            Console.WriteLine(json);

            Console.WriteLine();

        }

        public void Test()

        {

            Console.WriteLine("Newtonsoft.Json.Converters.XmlNodeConverter type information: ");

            Console.WriteLine(typeof(Newtonsoft.Json.Converters.XmlNodeConverter).Assembly.FullName);

            Console.WriteLine();

            Test(GetXml());

            var old = JsonConvert.DefaultSettings;

            try

            {

                JsonConvert.DefaultSettings = () => new JsonSerializerSettings

                {

                    Converters = { new FixedXmlNodeConverter() },

                };

                Console.WriteLine("Testing with global converter: ");

                Test(GetXml());

            }

            finally

            {

                JsonConvert.DefaultSettings = old;

            }

        }

        public String GetJson(XmlDocument xml)

        {

            return Newtonsoft.Json.JsonConvert.SerializeObject(xml, Newtonsoft.Json.Formatting.Indented);

        }       

        string GetXml()

        {

            string xml = @"<?xml version=""1.0"" encoding=""utf-8"" ?>

<root>

    <childNode>

        <innerChildNode>Some Text</innerChildNode>

    </childNode>

    <!-- H:011  T:134ms  S:1206  R:Tue May 02 07:59:03 PDT 2017  B:5.0.42642-master.3acb9f9~hotfix_pre.b72ccda  --> 

</root>

<!-- H:011  T:134ms  S:1206  R:Tue May 02 07:59:03 PDT 2017  B:5.0.42642-master.3acb9f9~hotfix_pre.b72ccda  -->";

            return xml;

        }

    }

​

    public class FixedXmlNodeConverter : Newtonsoft.Json.Converters.XmlNodeConverter

    {

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

        {

            base.WriteJson(writer, value, serializer);

            writer.WriteComment("Global Comment: H:011  T:134ms  S:1206  R:Tue May 02 07:59:03 PDT 2017  B:5.0.42642-master.3acb9f9~hotfix_pre.b72ccda");

        }

    }

​

    public class Program

    {

        public static void Main()

        {

            Console.WriteLine("Environment version: " + Environment.Version);

            Console.WriteLine("Json.NET version: " + typeof(JsonSerializer).Assembly.FullName);

            Console.WriteLine("");

            new TestClass().Test();

        }

    }

​