Services are a critical part of today’s (and tomorrow’s) application environments. You can use entities in service applications, and depending on your needs you can approach the task of using the Entity Framework with services in a number of ways. You can build your own Entity Framework logic into a Windows Communication Foundation (WCF) service, or use a framework that leverages it, such as WCF Data Services or WCF Rich Internet Applications (RIA) Data Services.
It is also possible to use entities in Active Server Method (ASMX) web services, which are still supported in Visual Studio 2010. You can download the ASMX sample created in the first edition of this book from the downloads page of the book’s website. Note, however, that the sample does not benefit from any of the new features of Entity Framework, such as foreign keys or POCO support.
In this chapter, we’ll take a look at all three scenarios. First,
you will write a WCF service that makes use of
EntityObject-based entities and learn about some
of the complications that arise (and their solutions) while you work
across the tiers of a distributed application. Even if you don’t plan to
write your services with
you will find a lot of useful information in this chapter. We’ll also take
a quick look at WCF Data Services and WCF RIA Services in order to get an
understanding of how they relate to the Entity Framework.
WCF Data Services and WCF RIA Services are Microsoft’s ...