MustUnderstandBehavior Class

Instructs Windows Communication Foundation (WCF) to disable the mandatory processing of headers not in the UnderstoodHeaders collection that must be understood according to the SOAP 1.1 and 1.2 specifications.

Namespace: System.ServiceModel.Description
Assembly: System.ServiceModel (in system.servicemodel.dll)

public class MustUnderstandBehavior : IEndpointBehavior
public class MustUnderstandBehavior implements IEndpointBehavior
public class MustUnderstandBehavior implements IEndpointBehavior
Not applicable.

By default the WCF client or service runtime throws an exception when it encounters a System.ServiceModel.Channels.MessageHeader in a message for which the MessageHeader.MustUnderstand property is true but the header is not in the MessageHeaders.UnderstoodHeaders property for the message.

To prevent this behavior, use the MustUnderstandBehavior and set the ValidateMustUnderstand property to false. Typically, this is used in scenarios where the message content is meant to be relayed somewhere else and not processed, such as a router service.


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

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0

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