XML C# Tutorial

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Xml;
using System.Xml.XPath;
    public class MainClass
    {
        public static void Main()
        {
            XmlDocument doc;
            XPathNavigator editor;
            XmlWriter writer;
            doc = new System.Xml.XmlDocument();
            doc.Load("pubs.xml");
            editor = doc.CreateNavigator().SelectSingleNode("/pubs");
            writer = editor.AppendChild();
            writer.WriteStartElement("publishers");
            writer.WriteAttributeString("pub_id", "1234");
            writer.WriteAttributeString("pub_name", "A");
            writer.WriteEndElement();
            writer.Close();
            doc.Save("output.xml");
        }
    }