JavaScript Pocket Reference

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JavaScript Pocket Reference

even when the user quits the browser, add an expiration date

using a string of the form:

name=value; expires=date

The expiration date should be in the form returned by Date.

toGMTString()

. If you want the cookie to be accessible to

other documents from your web site, you can specify a path

prefix:

name=value; expires=date; path=prefix

A single document may have more than one cookie associ-

ated with it. To query a document’s cookies, simply read the

value of the

cookie property. This string contains name=value

strings separated from each other by a semicolon and a

space. When reading cookies, you’ll never see a “path=” or

“expires=” clause; you’ll just get the cookie name and value.

Here’s a function that retrieves the value of a single named

cookie from the

cookie property. It assumes that cookie val-

ues never contain semicolons.

function getCookie(name) {

// Split cookies into an array

var cookies = document.cookie.split('; ');

for(var i = 0; i < cookies.length; i++) {

var c = cookies[i]; // One cookie

var pos = c.indexOf('='); // Find = sign

var n = c.substring(0,pos); // Get name

if (n == name) // If it matches

return c.substring(pos+1); // Return value

}

return null; // Can't find the named cookie

}

The W3C DOM

The W3C DOM standardizes most of the features of the leg-

acy DOM, but also adds important new ones. In addition to

supporting

forms[], images[], and other