MS .Net Framework 70-513

70 Questions | Total Attempts: 127

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DotNET Quizzes & Trivia

 70-513 - TS: Windows Communication Foundation Development via MS. NET Framework 4 Number of Questions Included: 145 Updated: 2012-05-28 This dump is the collection composed by Lyudmyla of all unique questions from dumps of BOB, FSAN and WASP, with Darths corrections.


Questions and Answers
  • 1. 
    You are creating a Windows Communication Foundation (WCF) service that is implemented as follows. (Line numbers are included for reference only.) 01 [ServiceContract] 02 [ServiceBehavior(IncludeExceptionDetailsInFaults = true)] 03 public class OrderService 04 { 05     [OperationContract] 06     public void SubmitOrder(Order anOrder) 07     { 08         try 09         { 10             ... 11         } 12         catch(DivideByZeroException ex) 13         { 14             ... 15         } 16     } 17 } You need to ensure that the stack trace details of the exception are not included in the error information sent to the client. What should you do?
    • A. 

      Replace line 14 with the following line: throw;

    • B. 

      Replace line 14 with the following line: throw new FaultException(anOrder, ex.ToString());

    • C. 

      After line 05, add the following line: [FaultContract(typeof(FaultException))] Replace line 14 with the following line: throw ex;

    • D. 

      Alter line 05, add the following line: [FaultContract(typeof(FaultException))] Replace line 14 with the following line: throw new FaultException(anOrder, "Divide by zero exception");

  • 2. 
    You are creating a Windows Communication Foundation (WCF) service. You do not want to expose the internal implementation at the service layer. You need to expose the following class as a service named Arithmetic with an operation named Sum: public class Calculator {     public int Add(int x, int y)     {     } } Which code segment should you use?
    • A. 

      [ServiceContract(Namespace="Arithmetic")] public class Calculator { [Operation Contract(Action="Sum")] public int Add(int x, int y) {} }

    • B. 

      [ServiceContract(ConfigurationName="Arithmetic")] public class Calculator { [Operation Contract(Action="Sum")] public int Add(int x, int y) {} }

    • C. 

      [ServiceContract(Name="Arithmetic")] public class Calculator { [OperationContract(Name="Sum")] public int Add(int x, int y) {} }

    • D. 

      [ServiceContract(Name="Arithmetic")] public class Calculator { [OperationContract(ReplyAction="Sum")] public int Add(int x, int y) {} }

  • 3. 
    You are developing a data contract for a Windows Communication Foundation (WCF) service. The data in the data contract must participate in round trips. Strict schema validity is not required. You need to ensure that the contract is forward-compatible and allows new data members to be added to it. Which interface should you implement in the data contract class?
    • A. 

      ICommunicationObject

    • B. 

      IExtension

    • C. 

      IExtensibleObject

    • D. 

      IExtensibleDataObject

  • 4. 
    A Windows Communication Foundation (WCF) application uses a data contract that has several data members. You need the application to throw a SerializationException if any of the data members are not present when a serialized instance of the data contract is deserialized. What should you do?
    • A. 

      Add the KnownType attribute to the data contract. Set a default value in each of the data member declarations.

    • B. 

      Add the KnownType attribute to the data contract. Set the Order property of each data member to unique integer value.

    • C. 

      Set the EmitDefaultValue property of each data member to false.

    • D. 

      Set the lsRequired property of each data member to true.

  • 5. 
    A Windows Communication Foundation (WCF) application uses the following data contract [DataContract] public class Person {     [DataMember]     public string firstName;     [DataMember]     public string lastName;     [DataMember]     public int age;     [DataMember]     public int ID;     } You need to ensure that the following XML segment is generated when the data contract is serialized. <Person>     <firstName xsi:nil="true"/>     <lastName xsi:nil="true"/>     <ID>999999999<ID> </Person> Which code segment should you use?
    • A. 

      [DataMember] public string firstName; [DataMember] public string lastName; [DataMember(EmitDefaultValue = true)] public int age = 0; [DataMember(EmitDefaultvValue = true)] public int ID = 999999999;

    • B. 

      [DataMember(EmitDefaultValue = false)] public string firstName = null; [DataMember(EmitDefaultValue = false)] public string lastName = null; [DataMember(EmitDefaultValue = true)] public int age = -1; [DataMember(EmitDefaultValue = false)] public int ID = 999999999;

    • C. 

      [DataMember(EmitDefaultValue = true)] public string firstName; [DataMember(EmitDefaultValue = true)] public string lastName; [DataMember(EmitDefaultValue = false)] public int age = -1; [DataMember(EmitDefaultValue = false)] public int ID = 999999999;

    • D. 

      [DataMember] public string firstName = null; [DataMember] public string lastName = null; [DataMember(EmitDefaultValue = false)] public int age = 0; [DataMember(EmitDefaultValue = false)] public int ID = 999999999;

  • 6. 
    The following is an example of a SOAP envelope.      <s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope">     <s:Header>         <h:StoreId xmlns:h="http://www.contoso.com">6495</h:StoreId>     </s:Header>     <s:Body>         <CheckStockRequest xmlns="http://www.contoso.com">             <ItemId>2469<ItemId>         </CheckStockRequest>     </s: Body> </s:Envelope> You need to create a message contract that generates the SOAP envelope. Which code segment should you use?
    • A. 

      [MessageContract(WrapperName="http://www.contoso.com")] public class CheckStockRequest { [MessageHeader(Namespace="http://www.contoso.com")] public int StoreId { get; set; } [MessageBodyMember(Namespace="http://www.contoso.com")] public int ItemId { get; set; } }

    • B. 

      [MessageContract(WrapperNamespace="http://www.contoso.com")] public class CheckStockRequest { [MessageHeader(Namespace="http://www.contoso.com")] public int StoreId { get; set; } [MessageBodyMember(Namespace="http://www contoso.com")] public int ItemId { get; set; } }

    • C. 

      [MessageContract(WrapperNamespace="http://www.contoso.com")] public class CheckStockRequest { [MessageHeader(Namespace="http://www.contoso.com")] public int StoreId { get; set; } public int ItemId { get; set; } }

    • D. 

      [MessageContract(WrapperNamespace="http://www.contoso.com")] public class CheckStockRequest { [MessageHeader(Namespace="http://www.contoso.com")] public int StoreId { get; set; } [MessageBodyMember] public int ItemId { get; set; } }

  • 7. 
    You are developing a client that sends several types of SOAP messages to a Windows Communication Foundation (WCF) service method named PostData. PostData is currently defined as follows: [OperationContract] void PostData(Order data); You need to modify PostData so that it can receive any SOAP message.  Which code segment should you use?
    • A. 

      [OperationContract(IsOneWay=true, Action="*", ReplyAction="*")] void PostData(Order data);

    • B. 

      [OperationContract(IsOneWay=true, Action="*", ReplyAction = "*")] void PostData(BodyWriter data);

    • C. 

      [OperationContract] void PostData(BodyWriter data);

    • D. 

      [OperationContract] void PostData(Message data);

  • 8. 
    A class named TestService implements the following interface:      [ServiceContract] public interface ITestService {     [OperationContract]     DateTime GetServiceTime(); } TestService is hosted in an ASP.NET application. You need to modify the application to allow the GetServiceTime method to return the data formatted as JSON. It must do this only when the request URL ends in /ServiceTime. What should you do?
    • A. 

      Add this attribute to the GetServiceTime method. [WebInvoke(Method="POST")] In the web.config file, add this element to system.serviceModel/behaviors/endpointBehaviors. In the web.config file, configure TestService in the system.serviceModel/services collection as follows:

    • B. 

      Add this attribute to the GetServiceTime method. [WebInvoke(Method="GET", UriTemplate="/ServiceTime", ResponseFormat=WebMessageFormat.Json)] In the web.config file, configure TestService in the system.serviceModel/services collection as follows:

    • C. 

      Add this attribute to the GetServiceTime method [WebGet(ResponseFormat=WebMessageFormat.Json, UriTemplate="/ServiceTime")] Create a new svc file named Jsonversion.svc with the following content.

    • D. 

      Add this attribute to the GetServiceTime method. [WebGet(UriTemplate="Json)/ServiceTime")] Create a new .svc file named Jsonversion.svc with the following content

  • 9. 
    You are creating a Windows Communication Foundation (WCF) service that implements operations in a RESTful manner.   You need to add a delete operation. You implement the delete method as follows: void DeleteItems(string id); You need to configure WCF to call this method when the client calls the service with the HTTP DELETE operation.  What should you do?
    • A. 

      Add the WebInvoke(UriTemplate="/Items/{id}", Method="DELETE") attribute to the operation

    • B. 

      Add the HttpDelete atribute to the operation

    • C. 

      Replace the string parameter with a RemovedActivityAction parameter

    • D. 

      Replace the return type with RemovedActivityAction.

  • 10. 
    A Windows Communication Foundation (WCF) service uses the following service contract. [ServiceContract] public interface IService {     [OperationContract]     string Operation1(string s); } You need to ensure that the operation contract Operation1 responds to HTTP POST requests. Which code segment should you use?
    • A. 

      [OperationContract] [WebInvoke(Method="POST")] string Operation1(string s);

    • B. 

      [OperationContract] [WebGet(UriTemplate="POST")] string Operation1(string s);

    • C. 

      [OperationContract(ReplyAction="POST")] string Operation1(string s);

    • D. 

      [OperationContract(Action="POST")] string Operation1(string s);

  • 11. 
    A Windows Communication Foundation (WCF) service implements a contract with one-way and request-reply operations. The service is exposed over a TCP transport. Clients use a router to communicate with the service. The router is implemented as follows.  (Line numbers are included for reference only.) 01 ServiceHost host = new ServiceHost(typeof(RoutingService)); 02 host.AddServiceEndpoint( 03     typeof(ISimplexDatagramRouter), 04     new NetTcpBinding(), "net.tcp://localhost/Router" 05    ); 06 List<ServiceEndpoint> lep = new List<ServiceEndpoint>(); 07 lep.Add( 08     new ServiceEndpoint( 09        ContractDescription.GetContract( 10           typeof(ISimplexDatagramRouter) 11    ), 12     new NetTcpBinding(), 13     new EndpointAddress("net.tcp://localhost:8080/Logger") 14    ) 15 ); 16 RoutingConfiguration rc = new RoutingConfiguration(); 17 rc.FilterTable.Add(new MatchAllMessageFilter(), lep); 18 host.Description.Behaviors.Add(new RoutingBehavior(rc)); Request-reply operations are failing. You need to ensure that the router can handle one-way and request-reply operations. What should you do?
    • A. 

      Change line 03 as follows: typeof(IRequestReplyRouter),

    • B. 

      Change line 03 as follows: typeof(IDuplexSessionRouter),

    • C. 

      Change line 10 as follows: typeof(IRequestReplyRouter)

    • D. 

      Change line 10 as follows: typeof(IDuplexSessionRouter)

  • 12. 
    You are modifying an existing Windows Communication Foundation (WCF) service that is defined as follows: [ServiceContract] public interface IMessageProcessor {     [OperationContract]     void ProcessMessages(); } public class MessageProcessor: IMessageProcessor     {      public void ProcessMessage();      SubmitOrder(); } SubmitOrder makes a call to another service. The ProcessMessage method does not perform as expected under a heavy load. You need to enable processing of multiple messages. New messages must only be processed when the ProcessMessage method is not processing requests, or when it is waiting for calls to SubmitOrder to return. Which attribute should you apply to the MessageProcessor class?
    • A. 

      CallbackBehavior(ConcurrencyMode=ConcurencyMode.Reentrant)

    • B. 

      CallbackBehavior(ConcurrencyMode=ConcurrencyMode.Multiple)

    • C. 

      ServiceBehavior(ConcurrencyMode=ConcurrencyMode.Reentrant)

    • D. 

      ServiceBehavior(ConcurrencyMode=ConcurrencyMode.Multiple)

  • 13. 
    A Windows Communication Foundation (WCF) service listens for messages at net.tcp://www.contoso.com/MyService. It has a logical address at http://www.contoso.com/MyService. The configuration for the WCF client is as follows: <endpoint address="http://www.contoso.com/MyService"     binding="netTcpBinding"     bindingConfiguraton="NetTcpBinding_IMyService"     contract="ServiceReference1.IMyService"     name="NetTcpBinding_IMyService"/> The generated configuration does not provide enough information for the client to communicate with the server. You need to update the client so that it can communicate with the server. What should you do?
    • A. 

      In the client configuration, change the value of the address attribute to net.tcp://www.contoso.com/MyService

    • B. 

      In the client configuration, change the value of the address attribute to net.tcp://www.contoso.com/MyService listen=http://www.contoso.com/MyService.

    • C. 

      After instantiating the client and before invoking any service operation, add this line of code. EndpointBehaviors.Add(new EndpointDiscoveryBehavior(){ Enabled = true });

    • D. 

      After instantiating the client and before invoking any service operation, add this line of code. client.Endpoint.Behaviors.Add(new ClientViaBehavior(new Uri("net.tcp://www.contoso.com/IMyService")));

  • 14. 
    A Windows Communication Foundation (WCF) service is self-hosted in a console application. The service implements the IDataAccess contract, which is defined in the MyApplication namespace. The service is implemented in a class named DataAccessService which implements the IDataAccess interface and also is defined in the MyApplication namespace.  The hosting code is as follows. (Line numbers are included for reference only.) 01 static void Main(string[] args) 02 { 03     ServiceHost host; 04     ... 05     host.Open(); 06     Console.ReadLine(); 07     host.Close(); 08 } You need to create a ServiceHost instance and assign it to the host variable. You also need to instantiate the service host. Which line of code should you insert at line 04?
    • A. 

      Host = new ServiceHost("MyApplication.DataAccessService");

    • B. 

      Host = new ServiceHost("MyApplication.DataAccess");

    • C. 

      Host = new ServiceHost(typeof(IDataAccess));

    • D. 

      Host = new ServiceHost(typeof(DataAccessService));

  • 15. 
    A Windows Communication Foundation (WCF) service implements the following contract. [ServiceContract] public interface IHelloService {     [OperationContract(WebGet(UriTemplate="hello?name={name}"))]     string SayHello(string name); } The implementation is as follows: public class HelloService: IHelloService {      public string SayHello(string name)      {         return "Hello " + name;      } } The service is self-hosted, and the hosting code is as follows: WebServiceHost svcHost = CreateHost(); svcHost.Open(); Console.ReadLine(); svcHost.Close(); You need to implement CreateHost so that the service has a single endpoint hosted at http://localhost:8000/HelloService. Which code segment should you use?
    • A. 

      WebServiceHost svcHost = new WebServiceHost(typeof(HelloService)); svcHost.AddServiceEndpoint(typeof(IHelloService), new WebHttpBinding(WebHttpSecurityMode.None), "http://localhost:8000/HelloService"); return svcHost;

    • B. 

      Uri baseAddress = new Uri("http://localhost:8000"); WebServiceHost svcHost = new WebServiceHost(typeof(HelloService), baseAddress); svcHost.AddServiceEndpoint(typeof(IHelloService), new WebHttpBinding(WebHttpSecurityMode.None), "HelloService"); return svcHost;

    • C. 

      WebServiceHost svcHost = new WebServiceHost(new HelloService()); svcHost.AddServiceEndpoint(typeof(IHelloService), new WebHttpBinding(WebHttpSecurityMode.None), "http://localhost:8000/HelloService"); retumn svcHost

    • D. 

      Uri baseAddress = new Uri("http://localhost:8000/"); WebServiceHost svcHost = new WebServiceHost(new HelloService(), baseAddress); svcHost.AddServiceEndpoint(typeof(IHelloService), new WebHttpBinding(WebHttpSecurityMode.None), "HelloService"); retumn svcHost;

  • 16. 
    You are building a client for a Windows Communication Foundation (WCF) service. You need to create a proxy to consume this service. Which class should you use?
    • A. 

      ChannelFactory

    • B. 

      ServiceHost

    • C. 

      ClientRuntime

    • D. 

      CommunicationObject

  • 17. 
    You are working with a Windows Communication Foundation (WCF) client application that has a generated proxy named SampleServiceProxy. When the client application is executing, in line 04 of the following code, the channel faults (Line numbers are included for reference only.)      01 SampleServiceProxy proxy = new SampleServiceProxy(); 02 try 03 { 04     proxy.ProcessInvoice(invoice); 05 } 06 catch 07 { 08     if(proxy.State == CommunicationState.Faulted) 09     { 10         ... 11     } 12 } 13 proxy.UpdateCustomer(customer); You need to return proxy to a state in which it can successfully execute the call in line 13. Which code segment should you use at line 10?
    • A. 

      Proxy.Close();

    • B. 

      Proxy = new SampleServiceProxy();

    • C. 

      Proxy.Abort();

    • D. 

      Proxy.Open();

  • 18. 
    A Windows Communication Foundation (WCF) service has a callback contract. You are developing a client application that will call this service. You must ensure that the client application can interact with the WCF service. What should you do?
    • A. 

      On the OperationContractAttribute, set the AsyncPattern property value to true.

    • B. 

      On the OperationContractAttribute, set the ReplyAction property value to the endpoint address of the client.

    • C. 

      On the client, create a proxy derived from DuplexClientBase.

    • D. 

      On the client, use GetCallbackChannel.

  • 19. 
    You are creating a Windows Communication Foundation (WCF) service. You have the following requirements: Messages must be sent over TCP The service must support transactions. Messages must be encoded using a binary encoding Messages must be secured using Windows stream-based security. You need to implement a custom binding for the service. In which order should the binding stack be configured?
    • A. 

      TcpTransport, windowsStreamSecurity, transactionFlow, binaryMessageEncoding

    • B. 

      TransactionFlow, binaryMessageEncoding, windowsStreamSecurity, tcpTransport

    • C. 

      WindowsStreamSecurity, tcpTransport, binaryMessageEncoding, transactionFlow

    • D. 

      BinaryMessageEncoding, transactionFlow, tcpTransport, windowsStreamSecurity

  • 20. 
    A Windows Communication Foundation (WCF) client configuration file contains the following XML segment in the system.serviceModel element. <client>     <endpoint address="net.tcp://server/ContosoService"         binding="netTcpBinding"         contract="Contoso.IContosoService"         name="netTcp"/>     <endpoint address="net.pipe://localhost/ContosoService"         binding="netNamedPipeBinding"         contract="Contoso.IContosoService"         name="netPipe" /> </client> You need to create a channel factory that can send messages to the endpoint listening at net.pipe://localhost/ContosoService. Which code segment should you use?
    • A. 

      ChannelFactory factory = new ChannelFactory("Contoso.IContoso");

    • B. 

      ChannelFactory factory = new ChannelFactory("netNamedPipeBinding");

    • C. 

      ChannelFactory factory = new ChannelFactory("netPipe");

    • D. 

      ChannelFactory factory = new ChannelFactory("net.pipe//localhost/ContosoService");

  • 21. 
    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 InstanceContext callbackContext = new InstanceContext(new NameService("client")); 23 ... 24 ... 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. 

      Change line 25 to the following code segment: DuplexChannelFactory factory = new DuplexChannelFactory(callbackContext, binding, address);

    • B. 

      Change line 26 to the following code segment: IGreetingService greetingServicefactory = CreateChannel(callbackContext);

    • C. 

      Add the following code segment after line 26: callbackContext.IncomingChannels.Add((IDuplexChannel)greetingService);

    • D. 

      Add the following code segment after line 26: callbackContext.OutgoingChannels.Add((IDuplexChannel)greetingService);

  • 22. 
    A Windows Communication Foundation (WCF) solution exposes the following contract over an HTTP connection. [ServiceContract] public interface IDataService {     [OperationContract]     string GetData(); } Existing clients are making blocking calls to GetData.  Calls to GetData take five seconds to complete. You need to allow new clients to issue non-blocking calls to get the data, without breaking any existing clients. What should you do?
    • A. 

      Replace the service interface with the following interface and implement the new methods. [ServiceContract] public interface IDoSomething { [OperationContract] string DoLongOperation(); [OperationContract(AsyncPattern = true)] IAsyncResult BeginDoLongOperation(); [OperationContract(AsyncPattern = true)] string EndDoLongOperation(IAsyncResult result); }

    • B. 

      Replace the service interface with the following interface and implement the new methods. [ServiceContract] public interface IDoSomething { [OperationContract(AsyncPattern = true)] IAsyncResult BeginDoLongOperation(); [OperationContract(AsyncPattern = true)] string EndDoLongOperation(IAsyncResult result); }

    • C. 

      Generate a proxy class with asynchronous methods and use it for the new clients.

    • D. 

      Add a new endpoint to the service that uses a full-duplex binding and use it for the new clients.

  • 23. 
    A Windows Communication Foundation (WCF) service implements the following contract. (Line numbers are included for reference only.) 01 [ServiceContract] 02 public interface IDataAccessService 03 { 04     [OperationContract] 05     void PutMessage(string message); 06     ... 07     [OperationContract] 08     [FaultContract(typeof(TimeoutFaultException))] 09     [FaultContract(typeof(FaultException))] 10     string SearchMessages(string search); 11 } The implementation of the SearchMessages method throws TimeoutFaultException exceptions for database timeouts. The implementation of the SearchMessages method also throws an Exception for any other issue it encounters while processing the request. These exceptions are received on the client side as generic FaultException exceptions. You need to implement the error handling code for SearchMessages and create a new channel on the client only if the channel faults. What should you do?
    • A. 

      Catch and handle both TimeoutFaultException and FaultException.

    • B. 

      Catch both TimeoutFaultException and FaultException. Create a new channel in both cases.

    • C. 

      Catch and handle TimeoutFaultException. Catch FaultException and create a new channel.

    • D. 

      Catch and handle FaultException. Catch TimeoutFaultException and create a new channel.

  • 24. 
    You are consuming a Windows Communication Foundation (WCF) service in an ASP. NET Web application. The service interface is defined as follows: [ServiceContract] public interface ICatalog {     [OperationContract]     [WebGet(UriTemplate="/Catalog/Items/{id}", ResponseFormat=WebMessageFormat.Json)]     string RetrieveItemDescription(int id); } The service is hosted at Catalogsvc. You need to call the service using jQuery to retrieve the description of an item as indicated by a variable named itemId. Which code segment should you use?
    • A. 

      $get(String.format("/Catalogsvc/Catalog/Items/id{0}", itemId) null, function (data) { ... }, javascript");

    • B. 

      $get(String.format("/Catalogsvc/Catalog/Items/{0}", itemId), null, function (data) { ... }, "json");

    • C. 

      $get(String.format("/Catalogsvc/Catalog/Items/{0}", itemld), null, function (data) { ... }, "xml");

    • D. 

      $get(String.format("/Catalogsvc/Catalog/Items/id{0}", itemld), null, function (data) { ... }, "json");

  • 25. 
    You are consuming a Windows Communication Foundation (WCF) service. The service interface is defined as follows: [DataContract(Namespace = ''] public class Item { } [ServiceContract(Namespace = '')] public interface Catalog {      [OperationContract]           [WebInvoke(Method="POST", UriTemplate="{Item}")]       Item UpdateItem(Item item); } The client application receives a WebResponse named response with the response from the service. You need to deserialize this response into a strongly typed object representing the return value of the method. Which code segment should you use?
    • A. 

      DataContractSerializer s = new DataContractSerializer(typeof(Item)); Item item = s.ReadObject(response.GetResponseStream()) as Item;

    • B. 

      BinaryFormatter f = new BinaryFormatter(); Item item = f.Deserialize(response.GetResponseStream() as Item;

    • C. 

      XmlDictionaryReader r = JsonReaderWriterFactory.CreateJsonReader(response.GetResponseStream(), XmlDictionaryReaderQuotas.Max); DataContractSerializer s = new DataContractSerializer(typeof(Item)); Item item = s.ReadObject(r) as Item;

    • D. 

      DataContractJsonSerializer s = new DataContractJsonSerializer(typeof(Item)); Item item = s.ReadObject(response.GetResponseStream()) as Item;

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