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

​

//https://stackoverflow.com/questions/77204552/c-sharp-xml-how-to-serialize-a-field-without-nesting-its-contents-inside-a-tag

​

    public class CustomExpression

    {

        [XmlAttribute] public string callFormat;

        [XmlAttribute] public string format;

        [XmlAttribute] public string name;

        [XmlAttribute] public string style;

​

        [XmlElement("BinaryOp", typeof(BinaryOp)) /* other subclasses */]

        [XmlElement("SomeOtherOp", typeof(SomeOtherOp)) /* other subclasses */]

        public VzExpression child;

​

​

        /* constructor and methods */

    }

​

    [XmlInclude(typeof(BinaryOp)) /* other subclasses */]

    public abstract class VzExpression {}

​

    public class BinaryOp : VzExpression { /* impl */ }

    public class SomeOtherOp : VzExpression { /* impl */ }

​

    public class TestClass

    {

        public static void Test()

        {

            var expression = new CustomExpression

            {

                callFormat = "",

                format = "",

                name = "",

                style = "",

                child = new BinaryOp(),

            };

            var xml = expression.GetXml(omitStandardNamespaces : true);

            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())).Serialize(xmlWriter, obj, ns);

                return textWriter.ToString();

            }

        }

    }

    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;

            }

        }

    }

​