MCSD Windows Communication Foundation (WCF) 2

Question 1

Which attribute marks a class as serializable for transfer in WCF messages?

Accepted Answer

[DataContract]

Answer

[DataContract] marks a class as a data transfer object whose members decorated with [DataMember] will be serialized by the DataContractSerializer.

Question 2

What is the purpose of the [KnownType] attribute in WCF?

Accepted Answer

Declares derived types that the serializer should recognize for polymorphic serialization

Answer

[KnownType] tells the DataContractSerializer about derived types of a base type so polymorphic objects can be properly serialized and deserialized.

Question 3

Which WCF binding supports WS-Security, reliable messaging, and transactions over HTTP?

Accepted Answer

WSHttpBinding

Answer

WSHttpBinding implements WS-* standards including WS-Security, WS-ReliableMessaging, and WS-AtomicTransaction over HTTP.

Question 4

Which WCF binding is used to create REST/JSON endpoints instead of SOAP endpoints?

Accepted Answer

WebHttpBinding

Answer

WebHttpBinding enables WCF services to expose REST-style endpoints responding to HTTP verbs (GET, POST, etc.) with JSON or XML.

Question 5

What does setting InstanceContextMode to PerCall mean in WCF service behavior?

Accepted Answer

A new service instance is created for each incoming operation call

Answer

PerCall creates a new service instance for every operation call, disposing it after the call completes, which is stateless and thread-safe by default.

MCSD Exam Practice Test

MCSD Exam Practice Test

MCSD Windows Communication Foundation (WCF) 2