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/77171943/c-sharp-xml-serialization-seralizizing-nullable-value-types-want-to-suppress

​

    public class SomeObject

    {

        [XmlElement(IsNullable = false)]

        public int? Foo { get; set; }

        public string? Bar { get; set; }

    }

​

    public class TestClass

    {

        public static void Test()

        {

            var obj = new SomeObject();

            var xml = obj.GetXml();

            Console.WriteLine(xml);

        }

    }

​

    public static class XmlSerializationHelper

    {

        public static T? LoadFromXml<T>(this string xmlString, XmlSerializer? serial = null)

        {

            using (var reader = new StringReader(xmlString))

            {

                return (T?)(serial ?? new XmlSerializer(typeof(T))).Deserialize(reader);

            }

        }

​

        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 static string? GetOuterXml(this XmlNode node, bool indent = true)

        {

            if (node == null)

                return null;

            using (var textWriter = new StringWriter())

            {

                var settings = new XmlWriterSettings

                {

                    Indent = indent,

                    OmitXmlDeclaration = true,

                };

                using (var xmlWriter = XmlWriter.Create(textWriter, settings))

                {

                    node.WriteTo(xmlWriter);

                }

                return textWriter.ToString();

            }

        }

    }

​

    public static class XmlAssert

    {

        // https://weblogs.asp.net/marianor/easy-way-to-compare-two-xmls-for-equality

        // https://stackoverflow.com/questions/7318157/best-way-to-compare-xelement-objects

        // Adapted from the answer https://stackoverflow.com/a/14463137 by https://stackoverflow.com/users/1102100/robjohnson

        public static void AreEqual(

            XElement expected,

            XElement actual)

        {

            Assert.IsTrue(XNode.DeepEquals(Normalize(expected), Normalize(actual)));

        }

​

        private static XElement Normalize(XElement element)

        {

            if (element.HasElements)

            {

                return new XElement(

                    element.Name,

                    element.Attributes()

                           .OrderBy(a => a.Name.ToString()),

                    element.Elements()

                           .OrderBy(a => a.Name.ToString())

                           .Select(e => Normalize(e)));

​

            }

​

            if (element.IsEmpty)

            {

                return new XElement(

                    element.Name,

                    element.Attributes()

                           .OrderBy(a => a.Name.ToString()));

            }

​

            return new XElement(element.Name, element.Attributes()

                .OrderBy(a => a.Name.ToString()), element.Value);

        }

    }

    public class Program

    {

        public static void Main()

        {

            Console.WriteLine("Environment version: {0} ({1}, {2}, NewLine: {3}).", 

                              System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription , Environment.Version, Environment.OSVersion,

                              System.Text.Json.JsonSerializer.Serialize(Environment.NewLine));

            Console.WriteLine();

​

            try

            {

                TestClass.Test();

            }

            catch (Exception ex)

            {

                Console.WriteLine("Failed with unhandled exception: ");

                Console.WriteLine(ex);

                throw;

            }

        }

    }

​