vb.net qr code open source SEND AND RECEIVE in Visual Basic .NET

Printer DataMatrix in Visual Basic .NET SEND AND RECEIVE

BranchID = Guid.NewGuid(); } public Branch(String name, String address, Guid id) { BranchName = name; Address = address; BranchID = id; } public Branch(String name, String address, String id) { BranchName = name; Address = address; BranchID = new Guid(id); } #endregion Constructors } The Branch class has three members to store the branch name, network address, and unique identifier. Several constructors are provided for ease of use. I added the region markers around the constructors so they can be collapsed to make the code more readable. Now add the definition of the ReservationRequest class, as shown in Listing 8-2. Listing 8-2. ReservationRequest Class Implementation /*****************************************************/ // Define the request message, ReservationRequest /*****************************************************/ [MessageContract(IsWrapped = false)] public class ReservationRequest { private String _ISBN; private String _Title; private String _Author; private Guid _RequestID; private Branch _Requester; private Guid _InstanceID; #region Constructors public ReservationRequest() { } public ReservationRequest(String title, String author, String isbn, Branch requestor) { _Title = title; _Author = author; _ISBN = isbn; _Requester = requestor;

_RequestID = Guid.NewGuid(); } public ReservationRequest(String title, String author, String isbn, Branch requestor, Guid id) { _Title = title; _Author = author; _ISBN = isbn; _Requester = requestor; _RequestID = id; } #endregion Constructors #region Public Properties [MessageBodyMember] public String Title { get { return _Title; } set { _Title = value; } } [MessageBodyMember] public String ISBN { get { return _ISBN; } set { _ISBN = value; } } [MessageBodyMember] public String Author { get { return _Author; } set { _Author = value; } } [MessageBodyMember] public Guid RequestID { get { return _RequestID; } set { _RequestID = value; } } [MessageBodyMember] public Branch Requester { get { return _Requester; } set { _Requester = value; } } [MessageBodyMember]

public Guid InstanceID { get { return _InstanceID; } set { _InstanceID = value; } } #endregion Public Properties } The ReservationRequest class contains the ISBN, Title, and Author members for defining the book that is being requested. It also includes a Branch class that represents the branch that is requesting the book.

Because the ReservationRequest class will be used to define the outgoing message, the MessageContract attribute indicates that this class will be included in a SOAP envelope. When using SOAP, messages are sent using an XML-like markup language. This allows for greater platform interoperability between clients and servers. SOAP is a standard protocol supported by WCF. There is also a MessageBodyMember attribute on each of the public properties. This is needed by the WCF layer to properly format the SOAP message. Now enter the implementation for the ReservationResponse class, as shown in Listing 8-3. Listing 8-3. Implementation of the ReservationResponse class /*****************************************************/ // Define the request message, ReservationResponse /*****************************************************/ [MessageContract(IsWrapped = false)] public class ReservationResponse { private bool _Reserved; private Branch _Provider; private Guid _RequestID; #region Constructors public ReservationResponse() { } public ReservationResponse(ReservationRequest request, bool reserved, Branch provider) { _RequestID = request.RequestID; _Reserved = reserved; _Provider = provider; } #endregion Constructors #region Public Properties

[MessageBodyMember] public bool Reserved { get { return _Reserved; } set { _Reserved = value; } } [MessageBodyMember] public Branch Provider { get { return _Provider; } set { _Provider = value; } } [MessageBodyMember] public Guid RequestID { get { return _RequestID; } set { _RequestID = value; } } #endregion Public Properties } The ReservationResponse class includes a Boolean member (Reserved) that indicates whether the book was available to be reserved. It also contains a Branch class that represents the branch that fulfilled the request.

To define a WCF endpoint, there are three pieces of information that must be specified: binding, address, and contract. The binding indicates the protocol that is used (such as HTTP, TCP, and so on). The address indicates where the endpoint can be found, and the type of address used will depend on the binding. For example, with HTTP binding, you would specify a URL. For TCP, the address would be a server name or an IP address. The contract is specified by a ServiceContract, which is an interface that defines the methods that are available at the endpoint. So far, you have defined the messages, which will be passed as parameters in the service methods. Now add the interface definition shown in Listing 8-4 to the same Reservation.cs file. Listing 8-4. Definition of the Service Contract /*****************************************************/ // Define the service contract, ILibraryReservation // which consists of two methods, RequestBook() and // RespondToRequest() /*****************************************************/ [ServiceContract] public interface ILibraryReservation {