XML C#

// Reading an XML document.
using System;
using System.Windows.Forms;
using System.Xml;
public class Test{
    static void Main() {
      XmlDocument document = new XmlDocument();
      document.Load( "books.xml" );
      XmlNodeReader reader = new XmlNodeReader( document );
      
      int depth = -1;
      while ( reader.Read() )
      {
         switch ( reader.NodeType )
         {
            case XmlNodeType.Element:
               depth++;
               TabOutput( depth );
               Console.WriteLine("<" + reader.Name + ">" + "\r\n");
               if ( reader.IsEmptyElement )
                  depth--;
               break;
            case XmlNodeType.Comment:
               TabOutput( depth );
               Console.WriteLine("\r\n");
               break;
            case XmlNodeType.Text:
               TabOutput( depth );
               Console.WriteLine("\t" + reader.Value + "\r\n");
               break;
            case XmlNodeType.XmlDeclaration:
               TabOutput( depth );
               Console.WriteLine("\r\n");
               break;
            
            case XmlNodeType.EndElement:     
               TabOutput( depth );
               Console.WriteLine("\r\n");
               depth--;    
               break;  
         }
      }
   } 
   static void TabOutput( int number )
   {
      for ( int i = 0; i < number; i++ )
         Console.Write("\t");
   }
}