Use a custom binding when one of the system-provided bindings does not meet the requirements of your service. A custom binding could be used, for example, to enable the use of a new transport or a new encoder at a service endpoint.

A custom binding is constructed using one of the CustomBinding from a collection of binding elements that are "stacked" in a specific order:

• At the top is an optional TransactionFlowBindingElement that allows flowing transactions.

• Next is an optional ReliableSessionBindingElement that provides a session and ordering mechanism as defined in the WS-ReliableMessaging specification. This notion of a session can cross SOAP and transport intermediaries.

• Next is an optional security binding element that provides security features like authorization, authentication, protection, and confidentiality. The following security binding elements are provided by Windows Communication Foundation (WCF):

  • SecurityBindingElement

  • AsymmetricSecurityBindingElement

  • SymmetricSecurityBindingElement

  • TransportSecurityBindingElement

• Next are the optional message-patterns specified by binding elements:

• CompositeDuplexBindingElement

• Next are the optional transport upgrades/helpers binding elements:

  • PnrpPeerResolverBindingElement

  • SslStreamSecurityBindingElement

  • WindowsStreamSecurityBindingElement

• Next is a required message encoding binding element. You can use your own transport or use one of the following message encoding bindings:

  • TextMessageEncodingBindingElement

  • BinaryMessageEncodingBindingElement

  • MtomMessageEncodingBindingElement

• At the bottom is a required transport element. You can use your own transport or use one of transport binding elements provided by Windows Communication Foundation (WCF):

  • TcpTransportBindingElement

  • NamedPipeTransportBindingElement

  • HttpTransportBindingElement

  • HttpsTransportBindingElement

  • MsmqTransportBindingElement

  • MsmqIntegrationBindingElement

  • PeerTransportBindingElement

The following table summarizes the options for each layer.

In addition, you can define your own binding elements and insert them between any of the preceding defined layers.

For a discussion on how to use a custom binding to modify a system-provided binding, see How To: Customize a System-Provided Binding.

The following example shows how to create a CustomBinding object using a ReliableSessionBindingElement and an HttpTransportBindingElement

Uri baseAddress = new Uri("http://localhost:8000/servicemodelsamples/service");

// Create a ServiceHost for the CalculatorService type and provide the base address.
using (ServiceHost serviceHost = new ServiceHost(typeof(CalculatorService), baseAddress))
{
    // Create a custom binding that contains two binding elements.
    ReliableSessionBindingElement reliableSession = new ReliableSessionBindingElement();
    reliableSession.Ordered = true;

    HttpTransportBindingElement httpTransport = new HttpTransportBindingElement();
    httpTransport.AuthenticationScheme = System.Net.AuthenticationSchemes.Anonymous;
    httpTransport.HostNameComparisonMode = HostNameComparisonMode.StrongWildcard;

    CustomBinding binding = new CustomBinding(reliableSession, httpTransport);

    // Add an endpoint using that binding.
    serviceHost.AddServiceEndpoint(typeof(ICalculator), binding, "");

    // Add a MEX endpoint.
    ServiceMetadataBehavior smb = new ServiceMetadataBehavior();
    smb.HttpGetEnabled = true;
    smb.HttpGetUrl = new Uri("http://localhost:8001/servicemodelsamples");
    serviceHost.Description.Behaviors.Add(smb);

    // Open the ServiceHostBase to create listeners and start listening for messages.
    serviceHost.Open();

    // The service can now be accessed.
    Console.WriteLine("The service is ready.");
    Console.WriteLine("Press <ENTER> to terminate service.");
    Console.WriteLine();
    Console.ReadLine();

    // Close the ServiceHostBase to shutdown the service.
    serviceHost.Close();
}

Windows Vista, Windows XP SP2, Windows Server 2003, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC

.NET Framework

.NET Compact Framework

Reference