using System;

using System.Collections.Generic;

using System.Text;

using System.Linq;

using System.Xml.Linq;

using System.Xml.Serialization;

using System.Xml;

using System.Xml.Linq;

using System.Xml.XPath;

using System.IO;

using System.Data;

using System.Runtime.Serialization;

using System.Runtime.Serialization.Formatters.Binary;

using System.IO.Compression;

​

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

​

//https://stackoverflow.com/questions/55084471/how-to-fetch-xml-node-based-on-value-of-sibling-node

​

    public class TestClass

    {

        public static void Test()

        {

            TestLinq(GetXml());

            TestXPath(GetXml());

        }

​

        static void TestLinq(string xmlString)

        {

            var root = XElement.Parse(xmlString);

            var title = "Hansel and Gretel";

            var query = root

                .Elements("Book")

                .Where(e => (string)e.Element("Title") == title)

                .Select(e => new 

                        {

                            Pages = (int)e.Element("Pages"),

                            Price = (decimal)e.Element("Price"),

                            Author = (string)e.Element("Author"),

                        });

            var results = query.ToList();

​

            Console.WriteLine("Result of LINQ query: ");

            Console.WriteLine(string.Join("\n", results));

        }

        static void TestXPath(string xmlString)

        {

            var root = XElement.Parse(xmlString);

            var title = "Hansel and Gretel";

            var query = root

                .XPathSelectElements(string.Format("/Book[Title='{0}']", title))

                .Select(e => new 

                        {

                            Pages = (int)e.Element("Pages"),

                            Price = (decimal)e.Element("Price"),

                            Author = (string)e.Element("Author"),

                        });

​

            var results = query.ToList();

​

            Console.WriteLine("Result of XPath query: ");

            Console.WriteLine(string.Join("\n", results));

        }

        static string GetXml()

        {

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

<Books>

  <Book>

    <Title>Hansel and Gretel</Title>

    <Pages>221</Pages>

    <Price>3.5</Price>

    <Author>Grimm</Author>

  </Book>

  <Book>

    <Title>Green Eggs and Ham</Title>

    <Pages>145</Pages>

    <Price>5.25</Price>

    <Author>Dr. Seuss</Author>

  </Book>

</Books>";

            return xml;

        }

    }

​

    public static class XmlSerializationHelper

    {

        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())).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("Roslyn 2.0 Compiler; Environment version: " + Environment.Version);

            Console.WriteLine();

​

            try

            {

                TestClass.Test();

            }

            catch (Exception ex)

            {

                Console.WriteLine("Uncaught exception: ");

                Console.WriteLine(ex);

                throw;

            }

        }

    }

​