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XPathMessageQuery Class

A message query that evaluates XPath expressions to retrieve data from a message.

Namespace:  System.ServiceModel
Assembly:  System.ServiceModel (in System.ServiceModel.dll)

<ContentPropertyAttribute("Expression")> _
Public Class XPathMessageQuery _
	Inherits MessageQuery

The XPathMessageQuery type exposes the following members.

Public methodXPathMessageQueryInitializes a new instance of the XPathMessageQuery class.
Public methodXPathMessageQuery(String)Initializes a new instance of the XPathMessageQuery class with the specified XPath expression.
Public methodXPathMessageQuery(String, XmlNamespaceManager)Initializes a new instance of the XPathMessageQuery class with the specified XPath expression and XmlNamespaceManager.
Public methodXPathMessageQuery(String, XsltContext)Initializes a new instance of the XPathMessageQuery class with the specified XPath expression and XsltContext.

Public propertyExpressionGets or sets the XPath expression for the XPathMessageQuery instance.
Public propertyNamespacesGets the XmlNamespaceManager associated with this XPathMessageQuery instance.

Public methodCreateMessageQueryCollectionCreates a message query collection that enables optimizations when executing multiple queries against a message. (Overrides MessageQuery.CreateMessageQueryCollection.)
Public methodEquals(Object)Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Public methodEvaluate(Of TResult)(Message)Evaluates the XPath query against the specified Message. (Overrides MessageQuery.Evaluate(Of TResult)(Message).)
Public methodEvaluate(Of TResult)(MessageBuffer)Evaluates the XPath query against the specified MessageBuffer. (Overrides MessageQuery.Evaluate(Of TResult)(MessageBuffer).)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeServes as a hash function for a particular type. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

The following example shows how to create a QueryCorrelationInitializer and specify a MessageQuerySet using a XPathMessageQuery.

new SendReply
    Request = submitPO,
    Content = SendContent.Create(new InArgument<int>( (e) => po.Get(e).Id)), // creates a SendMessageContent
    CorrelationInitializers =
        new QueryCorrelationInitializer
            // initializes a correlation based on the PurchaseOrder Id sent in the reply message and stores it in the handle
            CorrelationHandle = poidHandle,
            MessageQuerySet = new MessageQuerySet
                // int is the name of the parameter being sent in the outgoing response
                { "PoId", new XPathMessageQuery("sm:body()/ser:int", Constants.XPathMessageContext) }

.NET Framework

Supported in: 4

.NET Framework Client Profile

Supported in: 4

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.