XPathNavigator.WriteSubtree outputs node and its child nodes to the XmlWriter
/*
<?xml version="1.0" encoding="utf-8"?>
<book genre="Programming" publicationdate="2010" ISBN="1-111111-11-0" xmlns="http://www.domain.com/books">
<title>C#</title>
<author>
<first-name>A</first-name>
<last-name>B</last-name>
</author>
<price>8.99</price>
</book>
*/
using System;
using System.Linq;
using System.Xml;
using System.Xml.Linq;
using System.Collections;
using System.Collections.Generic;
using System.Xml.XPath;
public class MainClass{
public static void Main(){
XPathDocument document = new XPathDocument("domainBooks.xml");
XPathNavigator navigator = document.CreateNavigator();
navigator.MoveToChild("bookstore", "http://www.domain.com/books");
navigator.MoveToChild("book", "http://www.domain.com/books");
XmlWriter writer = XmlWriter.Create("domainBook.xml");
navigator.WriteSubtree(writer);
writer.Close();
}
}