Programming WCF Services

Working with Channels

You can use channels directly to invoke operations on the service without ever resorting to using a proxy class. The ChannelFactory<T> class (and its supporting types), shown in Example 1-21, enables you to create a proxy on the fly.

Example 1-21. TheChannelFactory<T> class

public class ContractDescription
{
   public Type ContractType
   {get;set;}
   //More members
}

public class ServiceEndpoint
{
   public ServiceEndpoint(ContractDescription contract,Binding binding,
                                                          EndpointAddress address);
   public EndpointAddress Address
   {get;set;}
   public Binding Binding
   {get;set;}
   public ContractDescription Contract
   {get;}
   //More members
}

public abstract class ChannelFactory : ...
{
   public ServiceEndpoint Endpoint
   {get;}
   //More members
}
public class ChannelFactory<T> : ChannelFactory,...
{
   public ChannelFactory(ServiceEndpoint endpoint);
   public ChannelFactory(string configurationName);
   public ChannelFactory(Binding binding,EndpointAddress endpointAddress);
   public static T CreateChannel(Binding binding,EndpointAddress endpointAddress);
   public T CreateChannel( );
   //More Members
}

You need to provide the constructor of ChannelFactory<T> with the endpoint—either the endpoint name from the client config file, or the binding and address objects, or a ServiceEndpoint object. Next, use the CreateChannel( ) method to obtain a reference to the proxy and use its methods. Finally, close the proxy by either casting it to IDisposable and calling the Dispose( ) method or to ICommunicationObject ...