Programming ASP.NET, Second Edition

Chapter 16. Creating Web Services

Chapter 15 provided an overview of web services, which are basically web applications with no user interface. Web services allow an application to make method calls against another application over the Internet as though it were calling a local dll.

There are two broad aspects to web service development: creating the web service and consuming the web service. This chapter covers the creation of web services. Chapter 17 covers the creation of web service client applications, also known as consumers.

Although a web service has no user interface and no visual component, the architecture and files used to create a web service are very similar to those used to create a web page, which are described in detail in Chapter 2 through Chapter 6. Some of these similarities include:

• Full implementation of the .NET Framework and Common Language Runtime (CLR), including the object-oriented architecture and all the base class libraries, as well as features such as caching, state, and data access

• Nearly identical file and code structures

• All source code files in plain text, which can be created in any text editor

• Full support by Visual Studio .NET, with all its productivity features, including IntelliSense, code completion, and integrated debugging

• Configurable on a global or application-wide basis using plain text configuration files

That said, web pages and web services are conceptually very different. A web page entails an interface designed for interaction with a person ...