Csharp/CSharp Tutorial/XML/XmlPathNavigator

Create XPathNavigator object by calling CreateNavigator of XmlDocument

<source lang="csharp">using System; using System.Xml.XPath; using System.Xml; class MainClass {

 static void Main(string[] args)
   {
       XmlDocument xmlDoc = new XmlDocument();
       xmlDoc.Load(@"c:\books.xml");
   
       XPathNavigator nav = xmlDoc.CreateNavigator();
       Console.WriteLine("Author First Name");
       XPathNodeIterator itrator = nav.Select("descendant::first-name");         
       while( itrator.MoveNext() )
       {
           Console.WriteLine(itrator.Current.Value.ToString());
       }
   }

}</source>

Get Node information by using XPathNavigator

<source lang="csharp">using System; using System.Xml.XPath; using System.Xml; class MainClass {

 static void Main(string[] args)
   {
       XmlDocument xmlDoc = new XmlDocument();
       xmlDoc.Load(@"c:\books.xml");
   
       XPathNavigator nav = xmlDoc.CreateNavigator();
       nav.MoveToRoot();
       string name = nav.Name;
       Console.WriteLine("Root node info: ");
       Console.WriteLine("Base URI" + nav.BaseURI.ToString());
       Console.WriteLine("Name: " +nav.Name.ToString());
       Console.WriteLine("Node Type: "+ nav.NodeType.ToString());
       Console.WriteLine("Node Value: "+nav.Value.ToString());
   
       if (nav.HasChildren)
       {
           nav.MoveToFirstChild();
           GetNodeInfo(nav);
       }
   }
   private static void GetNodeInfo( XPathNavigator nav1)
   {
       Console.WriteLine("Name: " +nav1.Name.ToString());
       Console.WriteLine("Node Type: "+ nav1.NodeType.ToString());
       Console.WriteLine("Node Value: "+nav1.Value.ToString());
   
       if (nav1.HasChildren)
       {
           nav1.MoveToFirstChild();
           
           while( nav1.MoveToNext() )
           {
               GetNodeInfo(nav1);
               nav1.MoveToParent();
           }               
       } else {   
           nav1.MoveToNext();
           GetNodeInfo(nav1);
       }
   }

}</source>

Select a node

<source lang="csharp">using System; using System.Xml.XPath; using System.Xml; class MainClass {

 static void Main(string[] args)
   {
       XmlDocument xmlDoc = new XmlDocument();
       xmlDoc.Load(@"c:\books.xml");
   
       XPathNavigator nav = xmlDoc.CreateNavigator();
       Console.WriteLine("Author First Name");
       XPathNodeIterator itrator = nav.Select("descendant::first-name");         
       while( itrator.MoveNext() )
       {
           Console.WriteLine(itrator.Current.Value.ToString());
       }
   }

}</source>

XPathNavigator: Evaluate

<source lang="csharp">using System; using System.Collections.Generic; using System.Text; using System.Xml; using System.Xml.XPath; class MainClass {

   static void Main(string[] args)
   {
       string xml = "<Order>" +
                       "<Item>" +
                           "<Description>Some widget part</Description>" +
                           "<Price>12.99</Price>" +
                       "</Item>" +
                       "<Item>" +
                           "<Description>Another widget</Description>" +
                           "<Price>50.12</Price>" +
                       "</Item>" +
                   "</Order>";
       XmlDocument doc = new XmlDocument();
       doc.LoadXml(xml);
       XPathNavigator nav = doc.CreateNavigator();
       Console.WriteLine("Total price for this order is ${0}", nav.Evaluate("sum(Order/Item/Price)"));
   }

}</source>

Total price for this order is $63.11

XPathNavigator: XPathNodeIterator with comparison

<source lang="csharp">using System; using System.Collections.Generic; using System.Text; using System.Xml; using System.Xml.XPath; class MainClass {

   static void Main(string[] args)
   {
       string xml = "<Order>" +
                       "<Item>" +
                           "<Description>widget part</Description>" +
                           "<Price>1.9</Price>" +
                       "</Item>" +
                       "<Item>" +
                           "<Description>Another widget</Description>" +
                           "<Price>5.2</Price>" +
                       "</Item>" +
                   "</Order>";
       XmlDocument doc = new XmlDocument();
       doc.LoadXml(xml);
       XPathNavigator nav = doc.CreateNavigator();
       XPathNodeIterator nodes = nav.Select("/Order/Item[Price>10]/Description");
       while (nodes.MoveNext())
       {
           Console.WriteLine("Item {0} has a price greater than 10",nodes.Current.Value);
       }
   }

}</source>

XPathNodeIterator from a select-node statement

<source lang="csharp">using System; using System.Xml.XPath; using System.Xml; class MainClass {

 static void Main(string[] args)
   {
       XmlDocument xmlDoc = new XmlDocument();
       xmlDoc.Load(@"c:\books.xml");
   
       XPathNavigator nav = xmlDoc.CreateNavigator();
       Console.WriteLine("Author First Name");
       XPathNodeIterator itrator = nav.Select("descendant::first-name");         
       while( itrator.MoveNext() )
       {
           Console.WriteLine(itrator.Current.Value.ToString());
       }
   }

}</source>