Page 227 - DCAP312_WEB_TECHNOLOGIES_II

Kumar Vishal, Lovely Professional University Unit 11: Web Services in Visual Studio .NET

Unit 11: Web Services in Visual Studio .NET Notes

CONTENTS

Objectives
Introduction
11.1 Creating Web Services
11.2 Expanding Web Application with Web Services
11.2.1 Web Applications Defined

11.2.2 How do Web Applications Work
11.2.3 Types of Web Applications
11.2.4 Technologies Used to Build Web Applications
11.3 Summary

11.4 Keywords
11.5 Review Questions
11.6 Further Readings

Objectives

After studying this unit, you will be able to:

• Explain about creating web services
• Expanding web application with web services

Introduction

A Web Service is programmable application logic available by normal Web protocols. One of
these Web protocols is the Simple Object Access Protocol (SOAP) that uses standards based
technologies (XML for data description and HTTP for transport) to inculcate and spread
application information.
Consumers of a Web Service do not require knowing anything about the stage, object model,
or indoctrination language used to implement the repair; they only need to recognize how to
send and be given SOAP messages (HTTP and XML).
Web Services are simple and easy to understand. It is possible, in fact, to author a simple
application that surfaces data as XML conforming to the SOAP specification. It would also be
relatively straightforward to build an application capable of receiving SOAP messages over HTTP
and deriving meaningful value out of it. For those of you familiar with PERL, this could simply
be a matter of using RegEx to parse the value out of the XML result; it is just another string.
However, just as we use frameworks such as ASP and ASP.NET to build Web applications, we
would much rather use a framework for building Web Services. The reasoning is quite logical.
We do not need to reinvent the plumbing—that is, at a high level, the capability to serialize our
data as XML, transport the data using HTTP, and de-serialize the XML back to meaningful data.
Instead, we want a framework that makes building Web Services easy, allowing us to focus on
the application logic not the plumbing. ASP.NET provides this framework for us.

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