Skip to Content
JavaScript: The Definitive Guide, Fourth Edition
book

JavaScript: The Definitive Guide, Fourth Edition

by David Flanagan
November 2001
Intermediate to advanced
936 pages
68h 43m
English
O'Reilly Media, Inc.
Content preview from JavaScript: The Definitive Guide, Fourth Edition

Name

Document.cookie — the cookie(s) of the document

Availability

JavaScript 1.0

Synopsis

                  document.cookie

Description

cookie is a string property that allows you to read, create, modify, and delete the cookie or cookies that apply to the current document. A cookie is a small amount of named data stored by the web browser. It gives web browsers a “memory” so they can use data input on one page in another page or recall user preferences across web browsing sessions. Cookie data is automatically transmitted between web browser and web server when appropriate so CGI scripts on the server end can read and write cookie values. Client-side JavaScript code can also read and write cookies with this property.

The Document.cookie property does not behave like a normal read/write property. You may both read and write the value of Document.cookie, but the value you read from this property is, in general, not the same as the value you write. For complete details on the use of this particularly complex property, see Chapter 16.

Usage

Cookies are intended for infrequent storage of small amounts of data. They are not intended as a general-purpose communication or programming mechanism, so use them in moderation. Note that web browsers are not required to retain the value of more than 20 cookies per web server (for the entire server, not just for your site on the server), nor to retain a cookie name/value pair of more than 4 KB in length.

See Also

Chapter 16

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.

Read now

Unlock full access

More than 5,000 organizations count on O’Reilly

AirBnbBlueOriginElectronic ArtsHomeDepotNasdaqRakutenTata Consultancy Services

QuotationMarkO’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.
Julian F.
Head of Cybersecurity
QuotationMarkI wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.
Addison B.
Field Engineer
QuotationMarkI’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.
Amir M.
Data Platform Tech Lead
QuotationMarkI'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Mark W.
Embedded Software Engineer

You might also like

JavaScript: The Definitive Guide, 5th Edition

JavaScript: The Definitive Guide, 5th Edition

David Flanagan

Publisher Resources

ISBN: 0596000480Catalog PageErrata