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CompositeDuplexBindingElement Class

Represents the binding element that is used when the client must expose an endpoint for the service to send messages back to the client.

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

Public NotInheritable Class CompositeDuplexBindingElement _
	Inherits BindingElement _
	Implements IPolicyExportExtension
Dim instance As CompositeDuplexBindingElement

This is commonly used with transports, such as HTTP, that do not allow duplex communications natively. TCP, by contrast, does allow duplex communications natively and so does not require the use of this binding element for the service to send messages back to a client.

The client must expose an address at which the service can contact it to establish a connection from the service to the client. This client address is provided by the ClientBaseAddress property. Note that Windows Communication Foundation (WCF) auto-generates a ClientBaseAddress if one is not explicitly set by the user.


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 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.

.NET Framework

Supported in: 3.5, 3.0