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Generation Denso QR Bar Code in C#.net Inside Out

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This le contains the de nition of an interface called IService. At the top of the IProductsService.cs le, you will nd using statements referencing the System, System. Collections.Generic, and System.Text namespaces (which you have met before), followed by two additional statements referencing the System.ServiceModel and System.Runtime. Serialization namespaces. The System.ServiceModel namespace contains the classes used by WCF for de ning services and their operations. WCF uses the classes in the System.Runtime.Serialization namespace to convert objects to a stream of data for transmission over the network (a process known as serialization) and to convert a stream of data received from the network back to objects (deserialization). You will learn a little about how WCF serializes and deserializes objects later in this chapter. The primary contents of the IProductsService le are an interface called IService and a class called CompositeType. The IService interface is pre xed with the ServiceContract attribute, and the CompositeType class is tagged with the DataContract attribute. Because of the structure of a WCF service, you can adopt a contract- rst approach to development. When performing contract- rst development, you de ne the interfaces, or contracts, that the service will implement, and then you build a service that conforms to these contracts. This is not a new technique, and you have seen examples of this strategy throughout this book. The point behind using contract- rst development is that you can concentrate on the design of your service. If necessary, it can quickly be reviewed to ensure that your design does not introduce any dependencies on speci c hardware or software before you perform too much development; remember that in many cases client applications might not be built using WCF and might not even be running on Windows. The ServiceContract attribute marks an interface as de ning methods that the class implementing the Web service will expose as Web methods. The methods themselves are tagged with the OperationContract attribute. The tools provided with Visual Studio 2008 use these attributes to help generate the appropriate WSDL document for the service. Any methods in the interface not marked with the OperationContract attribute will not be included in the WSDL document and therefore will not be accessible to client applications using the Web service. If a Web method takes parameters or returns a value, the data for these parameters and value must be converted to a format that can be transmitted over the network and then converted back again to objects this is the process known as serialization and deserialization mentioned earlier. The various Web services standards de ne mechanisms for specifying the serialized format of simple data types, such as numbers and strings, as part of the WSDL description for a Web service. However, you can also de ne your own complex data types based on classes and structures. If you make use of these types in a Web service, you must provide information on how to serialize and deserialize them. If you look at the de nition of the GetDataUsingDataContract method in the

Defines the style properties for every other row in the table Defines the style properties for the row being edited Defines the style properties for the grid s footer Defines the style properties for the grid s header Defines the style properties for the empty row, which is rendered when the GridView is bound to empty data sources Defines the style properties for the grid s pager Defines the style properties for the rows in the table Defines the style properties for the currently selected row

SQL Ser ver has t wo m ain k inds of securit y account s. The first k ind of secur it y account grant s access t o a dat abase serv er. SQL Serv er calls t his first k ind of secur it y account a login secur it y account or a login. The second kind of secur it y account grant s access t o a dat abase w it hin a serv er. SQL Serv er applies t he nam e user secur it y account or user t o t his k ind of secur it y account . User account s allow y our applicat ion s users t o gain access t o t he r esources t hat y ou creat e for t heir use on a SQL Ser v er inst ance. Any one login account can have m ult iple user secur it y account s associat ed w it h it one for each dat abase t o which t he login needs access. Ev er y SQL Ser ver inst ance m aint ains a collect ion of logins. A login is like a k ey t hat let s a user open t he door int o a SQL Serv er inst ance. There ar e t hree t ypes of logins. These t ypes of logins r elat e t o how SQL Server validat es a user. The

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<ComUnregisterFunction()>_ Private Shared Sub UnRegister(ByVal ty As Type) Registry.CurrentUser.DeleteSubKey(COMPANYKEY) End Sub

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<body> <div class="page"> <form id="Form1" runat="server"> ... <div class="main"> <asp:ContentPlaceHolder ID="MainContent" runat="server" /> </div> </form> <asp:ContentPlaceHolder ID="ExtraFormContent" runat="server" /> <div class="clear"> </div> <div class="footer"> </div> </div> </body>

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