XML/XPath: Difference between revisions

==[[Ruby]]==

#Example taken from the REXML tutorial (http://www.germane-software.com/software/rexml/docs/tutorial.html)

require "rexml/document"

include REXML

#create the REXML Document from the string (%q is Ruby's multiline string, everything between the two @-characters is the string)

doc = Document.new(

%q@<inventory title="OmniCorp Store #45x10^3">

...

</inventory>

@

)

# The invisibility cream is the first <item>

invisibility = XPath.first( doc, "//item" )

# Prints out all of the prices

XPath.each( doc, "//price") { |element| puts element.text }

# Gets an array of all of the "name" elements in the document.

names = XPath.match( doc, "//name" )

==[[C#]]==

XmlReader XReader;

// Either read the xml from a string ...

XReader = XmlReader.Create(new StringReader("<inventory title=... </inventory>"));

// ... or read it from the file system.

XReader = XmlReader.Create("xmlfile.xml");

// Create a XPathDocument object (which implements the IXPathNavigable interface)

// which is optimized for XPath operation. (very fast).

IXPathNavigable XDocument = new XPathDocument(XReader);

// Create a Navigator to navigate through the document.

XPathNavigator Nav = XDocument.CreateNavigator();

Nav = Nav.SelectSingleNode("//item");

// Move to the first element of the selection. (if available).

if(Nav.MoveToFirst())

Console.WriteLine(Nav.OuterXml); // The outer xml of the first item element.

// Get an iterator to loop over multiple selected nodes.

XPathNodeIterator Iterator = XDocument.CreateNavigator().Select("//price");

while (Iterator.MoveNext())

Console.WriteLine(Iterator.Current.Value);

Iterator = XDocument.CreateNavigator().Select("//name");

// Use a generic list.

List<string> NodesValues = new List<string>();

while (Iterator.MoveNext())

NodesValues.Add(Iterator.Current.Value);

// Convert the generic list to an array and output the count of items.

Console.WriteLine(NodesValues.ToArray().Length);