Converting XDocument to XmlDocument and vice versa

Converting XDocument to XmlDocument:

     To convert back and forth use the built in xDocument.CreateReader() and an XmlNodeReader. To make the work easy put that into Extension method.

using System;
using System.Xml;
using System.Xml.Linq;
 
namespace MyTest
{
  internal class Program
  {
  private static void Main(string[] args)
  {
 
      var xmlDocument = new XmlDocument();
      xmlDocument.LoadXml("<Root><Child>Test</Child></Root>");
 
      var xDocument = xmlDocument.ToXDocument();
      var newXmlDocument = xDocument.ToXmlDocument();
      Console.ReadLine();
    }
  }
 
  public static class DocumentExtensions
  {
    public static XmlDocument ToXmlDocument(this XDocument xDocument)
    {
      var xmlDocument = new XmlDocument();
      using(var xmlReader = xDocument.CreateReader())
      {
        xmlDocument.Load(xmlReader);
      }
      return xmlDocument;
    }
 
    public static XDocument ToXDocument(this XmlDocument xmlDocument)
    {
      using (var nodeReader = new XmlNodeReader(xmlDocument))
      {
        nodeReader.MoveToContent();
        return XDocument.Load(nodeReader);
      }
    }
  }
}

The source will provide further informations about XmlReader.

Simple code:

     For the convertion process of Xdocument to Xmldocument the below single line code will use,

XDocument y = XDocument.Parse(pXmldoc.OuterXml); // where pXmldoc is of type XMLDocument

Try  this code:

using System.Xml;
using System.Xml.Linq;
 
  #region Extention Method
  public static XElement ToXElement(this XmlElement element)
  {
    return XElement.Parse(element.OuterXml);
  }
 
  public static XmlElement ToXmlElement(this XElement element)
  {
    var doc = new XmlDocument();
    doc.LoadXml(element.ToString());
    return doc.DocumentElement;
  }
  #endregion

The Extention can be done simply using like,

System.Xml.XmlElement systemXml = (new XElement("nothing")).ToXmlElement();
System.Xml.Linq.XElement linqXml = systemXml.ToXElement();