https://stackoverflow.com/questions/76950645/c-sharp-deserialize-known-unknownelement-from-xml

CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;
using System.Text;
using System.Linq;
using System.Xml.Serialization;
using System.Xml;
using System.Xml.Linq;
using System.IO;
using System.Data;

using System.Text.Json;

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

#nullable enable

//https://stackoverflow.com/questions/76950645/c-sharp-deserialize-known-unknownelement-from-xml

    public class TestClass
    {
        public static void Test()
        {
			var s = "I'm from Foo.A";
			Console.WriteLine(s.GetXml(omitStandardNamespaces : true));
		}
    }

    public static partial class XmlExtensions
    {
        public static T? LoadFromXml<T>(this string xmlString, XmlSerializer? serial = null)
        {
            serial = serial ?? new XmlSerializer(typeof(T));
            using (var reader = new StringReader(xmlString))
            {
				return (T?)serial.Deserialize(reader);
            }
        }

        public static string GetXml<T>(this T obj, bool omitStandardNamespaces)
        {
			return obj.GetXml(null, omitStandardNamespaces);
        }
		
        public static string GetXml<T>(this T obj, XmlSerializer? serializer = null, bool omitStandardNamespaces = false)
        {
            XmlSerializerNamespaces? ns = null;
            if (omitStandardNamespaces)
            {
                ns = new XmlSerializerNamespaces();
                ns.Add("", ""); // Disable the xmlns:xsi and xmlns:xsd lines.
            }			
            using (var textWriter = new StringWriter())
            {
                var settings = new XmlWriterSettings() { Indent = true }; // For cosmetic purposes.
                using (var xmlWriter = XmlWriter.Create(textWriter, settings))
                    (serializer ?? new XmlSerializer(obj?.GetType() ?? typeof(T))).Serialize(xmlWriter, obj, ns);
                return textWriter.ToString();
            }
        }
    }

	public class Program
	{
		public static void Main()
		{
			Console.WriteLine("Environment version: {0} ({1}, {2})", System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription , Environment.Version, Environment.OSVersion);
			Console.WriteLine();

			try
			{
				TestClass.Test();
			}
			catch (Exception ex)
			{
				Console.WriteLine("Failed with unhandled exception: ");
				Console.WriteLine(ex);
				throw;
			}
		}
	}