C# 2008 Programmer's Reference

Chapter 20. Windows Communication Foundation

Windows Communication Foundation (WCF) is Microsoft's unified programming model for building service oriented applications (SOA). Parts of a service-oriented application can be exposed as a service that other applications can access.

WCF is a big topic, and it cannot be fully covered in a single chapter. However, this chapter provides a quick introduction to this new technology and shows how it addresses some of the limitations of today's technology. While most books and conference focused heavily on the theory behind WCF, this chapter shows you how to build WCF services and then explains the theory behind them.

In short, this chapter explores:

• How traditional ASMX Web Services differ from WCF

• The ABCs of WCF

• Building different types of WCF services

What Is WCF?

To understand the rationale behind WCF, it is important to understand the offerings that are available today. In previous versions of Visual Studio (Visual Studio 2005 and Visual Studio .NET 2003), you use the ASP.NET application model to you create ASMX XML Web Services that expose functionalities to clients who want to use them.

ASMX Web Services are still supported in Visual Studio 2008 for backward compatibility, but going forward Microsoft recommends that developers use WCF when building services.

To compare WCF and ASMX Web Services, let's first use Visual Studio 2008 to create a new ASP.NET Web Service Application project. Name the project StocksWS.

Populate the default Service1.asmx.cs ...