Extensions.XPathSelectElement Method (XNode, String, IXmlNamespaceResolver)


Selects an XElement using a XPath expression, resolving namespace prefixes using the specified IXmlNamespaceResolver.

Namespace:   System.Xml.XPath
Assembly:  System.Xml.Linq (in System.Xml.Linq.dll)

public static XElement XPathSelectElement(
	this XNode node,
	string expression,
	IXmlNamespaceResolver resolver


Type: System.Xml.Linq.XNode

The XNode on which to evaluate the XPath expression.

Type: System.String

A String that contains an XPath expression.

Type: System.Xml.IXmlNamespaceResolver

An IXmlNamespaceResolver for the namespace prefixes in the XPath expression.

Return Value

Type: System.Xml.Linq.XElement

An XElement, or null.

You can use this method to evaluate XPath expressions that contain namespace prefixes.

The following example creates an XML tree that contains a namespace. It uses an XmlReader to read the XML document. It then gets an XmlNameTable from the XmlReader, and an XmlNamespaceManager from the XmlNameTable. It uses the XmlNamespaceManager when selecting an element.

                string markup = @"
<aw:Root xmlns:aw='http://www.adventure-works.com'>
    <aw:Child1>child one data</aw:Child1>
    <aw:Child2>child two data</aw:Child2>
XmlReader reader = XmlReader.Create(new StringReader(markup));
XElement root = XElement.Load(reader);
XmlNameTable nameTable = reader.NameTable;
XmlNamespaceManager namespaceManager = new XmlNamespaceManager(nameTable);
namespaceManager.AddNamespace("aw", "http://www.adventure-works.com");
XElement child1 = root.XPathSelectElement("./aw:Child1", namespaceManager);

This example produces the following output:

<aw:Child1 xmlns:aw="http://www.adventure-works.com">child one data</aw:Child1>

.NET Framework
Available since 3.5
Available since 4.0
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