Using Web Services with ADO.NET

Abstract

Web services provide a way to run a service on the Web and access its methods using standard protocols, including Simple Object Access Protocol (SOAP), Extensible Markup Language (XML), Web Service Description Language (WSDL), and Hypertext Transfer Protocol (HTTP). Technically, a Web service is nothing more than an application that exposes its interface to a client who wants to access the service’s abilities. The uses of a Web service include validating credit cards, searching for data in a database, inserting an order into a shopping cart, and updating a guest list. The sky is the limit on what you can have your Web service do on your server. In the past, JavaBeans, ActiveX/Component Object Model (COM) controls, and other nonstandard service components handled these services, which required specialized formats to exchange data with the client. But Web services under .NET run by invoking methods in the service directly through HTTP or SOAP, so someone wanting to run your Web service from their computer at home can simply send an HTTP call to your service, passing the parameters in a standard Uniform Resource Locator (URL). I’ll show you how to do this later in the chapter.