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Mandeep Kaur, Lovely Professional University Unit 11: Using Request Objects

Unit 11: Using Request Objects Notes

CONTENTS
Objectives
Introduction

11.1 Standard HTTP Headers
11.2 Accessing Environmental Variables
11.3 Using Cookies

11.3.1 Practical Uses for Cookies
11.3.2 What Information can a Cookie Extract?
11.3.3 Advantages and Disadvantages of Using Cookies
11.4 Summary
11.5 Keywords

11.6 Review Questions
11.7 Further Readings

Objectives

After studying this unit, you will be able to:

 Recognize the standard HTTP headers
 Describe Environmental variables
 Demonstrate the Cookies

Introduction

The Request object can be used to get the information from the client HTTP header and body.
A HTTP header is a single piece of information, sent either from the client to the server or from
the server to the client, whenever a client request a page. The HTTP headers are useful for
obtaining information about the current visitor. This unit will introduce you to HTTP headers,
standard HTTP headers and how one can read these headers using the Request object. But we
need more than HTTP headers to tell about the web server or the asp page that is being requested
by the client, which leads us to environmental variables. Environmental variables contain
information such as the name of the web server, the URL of the currently processing ASP page,
or the name of the name of the web server software being used. Lastly you will learn about
using cookies and to write cookies using the Response Object. Retrieving the Results of a Form.

!
Caution The Request object retrieves the values that the client browser passed to the server
during an HTTP request.
Accessing the HTTP Headers (Useful HTTP Headers, Reading the HTTP Headers with Request,
Server Variables). In a client-server model, when client is a web browser communicating with
the server, requesting a web page.

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