XPathMessageContext Class
Defines several XPath functions and namespace mappings commonly used when evaluating XPath expressions against SOAP documents.
Assembly: System.ServiceModel (in System.ServiceModel.dll)
The XPath engine has full XPath context support and uses the .NET Framework's XsltContext class in the same way that XPathNavigator does to implement this support. XsltContext is an abstract class that allows developers to implement custom XPath function libraries and declare XPath variables. XsltContext is an XmlNamespaceManager and thus also contains the namespace prefix mappings.
The filter engine implements an XsltContext named XPathMessageContext. XPathMessageContext defines custom functions that can be used in XPath expressions and it declares several common namespace prefix mappings.
System.Xml.XmlNamespaceManager
System.Xml.Xsl.XsltContext
System.ServiceModel.Dispatcher.XPathMessageContext
Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.