JavaScript and Ajax for the Web: Visual QuickStart Guide, Seventh Edition

Baking Your First Cookie

A cookie is a text string with a particular format:

cookieName=cookieValue;
expires=expirationDateGMT; path=URLpath;
domain=siteDomain

Breaking this down, the first part of the string gives the cookie a name and assigns it a value. This is the only mandatory part of a cookie; the rest of the string is optional. Next is the expiration date of the cookie; when this date is reached, the browser automatically deletes the cookie. The expiration date is followed by a URL path, which lets you store a URL in the cookie. Finally, you can store a domain value in the cookie.

Script 10.1, the HTML file, calls the JavaScript in Script 10.2, which sets a cookie from a value entered by the user into a form. When you try this one out, ...