Chapter 4: Creating and Managing XML Web Services

Microsoft Exam Objectives Covered In This Chapter:

• Create and consume an XML Web service.

  • Control characteristics of Web methods by using attributes.

  • Control XML wire format for an XML Web service.

  • Instantiate and invoke an XML Web service.

  • Create asynchronous Web methods.

  • Create and use SOAP extensions.

XML Web services are one of the most talked about aspects of .NET development. They enable you to expose your application’s functionality to the widest possible range of users. XML Web services can be used when it is impossible to use .NET Remoting—because your XML Web services application runs on a web server accessible to the Internet, users do not have to be on the same platform or part of the same network to access your application. XML Web services are based on Internet standards, such as HTTP, XML, and SOAP, which enable your application to be visible and accessible to users on any platform. XML Web services give your applications the ability to access resources over the Internet with the ease, and that has made the World Wide Web so popular for searching and browsing.

This chapter covers the basics of creating and calling XML Web services by using Visual Studio .NET. You will learn how the .NET Framework enables attributes to be assigned to XML Web services and methods, how to call Web methods asynchronously, and how to extend basic Simple Object Access Protocol (SOAP) processing with custom SOAP headers and SOAP extensions.