A Windows Communication Foundation (WCF) solution uses the following contracts. (Line
numbers are included for reference only.) 01 [ServiceContract(CallbackContract =
typeof(INameService))] 02 public interface IGreetingService 03 { 04 [OperationContract] 05
string GetMessage(); 06 } 07 08 [ServiceContract] 09 public interface INameService 10 { 11
[OperationContract] 12 string GetName(); 13 } When the client calls GetMessage on the
service interface, the service calls GetName on the client callback. In the client, the class
NameService implements the callback contract. The client channel is created as follows. 22
In stanceContext callbackContext = new InstanceContext(new NameService(“client”)); 25
DuplexChannelFactory<IGreetingService> factory = new
DuplexChannelFactory<IGreetingService>( typeof(NameService), binding, address); 26
IGreetingService greetingService = factory.CreateChannel(); You need to ensure that the
service callback is processed by the instance of NameService. What are two possible ways
to achieve this goal? (Each correct answer presents a complete solution. Choose two.)
A.
Add the following code segment after line 26.
callbackContext.OutgoingChannels.Add((IDuplexChannel)greetingService);
B.
Add the following code segment after line 26.
callbackContext.IncomingChannels.Add((IDuplexChannel)greetingService);
C.
Change line 25 to the following code segment.
DuplexChannelFactory<IGreetingService> factory = new
DuplexChannelFactory<IGreetingService>( callbackContext, binding, address);
D.
Change line 26 to the following code segment. IGreetingService greetingService =
factory.CreateChannel(callbackContext);