JavaScript Cookies: Making the Most from the Drudgery of Others | 3

<HTML>

<HEAD>

<!--

// name - name of the cookie

// value - value of the cookie

// [expires] - expiration date of the cookie (defaults to end of current session)

// [path] - path for which the cookie is valid (defaults to path of calling document)

// [domain] - domain for which the cookie is valid (defaults to domain of calling document)

// [secure] - Boolean value indicating if the cookie transmission requires a secure transmission

// * an argument defaults when it is assigned null as a placeholder

// * a null placeholder is not required for trailing omitted arguments

function setCookie(name, value, expires, path, domain, secure) {

var curCookie = name + "=" + escape(value) +

((expires) ? "; expires=" + expires.toGMTString() : "") +

((path) ? "; path=" + path : "") +

((domain) ? "; domain=" + domain : "") +

((secure) ? "; secure" : "");

document.cookie = curCookie;

}

// name - name of the desired cookie

// * return string containing value of specified cookie or null if cookie does not exist

function getCookie(name) {

var dc = document.cookie;

var prefix = name + "=";

var begin = dc.indexOf("; " + prefix);

if (begin == -1) {

begin = dc.indexOf(prefix);

if (begin != 0) return null;

} else

begin += 2;

var end = document.cookie.indexOf(";", begin);

if (end == -1)

end = dc.length;

return unescape(dc.substring(begin + prefix.length, end));

}

// name - name of the cookie

// [path] - path of the cookie (must be same as path used to create cookie)

// [domain] - domain of the cookie (must be same as domain used to create cookie)

// * path and domain default if assigned null or omitted if no explicit argument proceeds

function deleteCookie(name, path, domain) {

if (getCookie(name)) {

document.cookie = name + "=" +

((path) ? "; path=" + path : "") +

((domain) ? "; domain=" + domain : "") +

"; expires=Thu, 01-Jan-70 00:00:01 GMT";

}

// date - any instance of the Date object

// * hand all instances of the Date object to this function for "repairs"

function fixDate(date) {

var base = new Date(0);

var skew = base.getTime();

if (skew > 0)

date.setTime(date.getTime() - skew);

}

// -->

</SCRIPT>

</HEAD>

<BODY>

<!--

// create an instance of the Date object

var now = new Date();

// fix the bug in Navigator 2.0, Macintosh

fixDate(now);

// cookie expires in one year (actually, 365 days)

// 365 days in a year// 24 hours in a day

// 60 minutes in an hour

// 60 seconds in a minute

// 1000 milliseconds in a second

now.setTime(now.getTime() + 365 * 24 * 60 * 60 * 1000);var username = getCookie("username");

// if the cookie wasn't found, ask for the name

if (!username) { username = prompt("Please enter your name:", "");}

// set the new cookie

setCookie("username", username, now);if (username) { document.write("Welcome to this page, " + username + "."); setCookie("username", username, now);} else document.write("You refused to enter your name.");// -->

</SCRIPT>

</BODY>

</HTML>

Comments are welcome
Produced by Greg Meckes

Created: Jan. 12, 2000
Revised: Jan. 12, 2000

URL: http://webreference.com/programming/javascript/cookies/

JavaScript Cookies: Making the Most from the Drudgery of Others | 3

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