The last step is to create the service interface layer. Again, the steps here are very similar to the steps in Chapter 5, Implementing a Three-layer WCF Service, so you can refer to this chapter for more details.
NorthwindBDOto this new service interface project.
NorthwindService, select Manage NuGet Packages… and then install Entity Framework.
IService1.cs, as follows:
IProductService.cs. This will also change the interface name ...