Read a javascript cookie by name

Question

I have set a cookie using

document.cookie = 
    \'MYBIGCOOKIE=\' + value + 
    \'; expires=\' + now.toGMTString() + 
    \'; path=/\';

No

Answer 1

Here is an example implementation, which would make this process seamless (Borrowed from AngularJs)

var CookieReader = (function(){
var lastCookies = {};
var lastCookieString = '';

function safeGetCookie() {
    try {
        return document.cookie || '';
    } catch (e) {
        return '';
    }
}

function safeDecodeURIComponent(str) {
    try {
        return decodeURIComponent(str);
    } catch (e) {
        return str;
    }
}

function isUndefined(value) {
    return typeof value === 'undefined';
}

return function () {
    var cookieArray, cookie, i, index, name;
    var currentCookieString = safeGetCookie();

    if (currentCookieString !== lastCookieString) {
        lastCookieString = currentCookieString;
        cookieArray = lastCookieString.split('; ');
        lastCookies = {};

        for (i = 0; i < cookieArray.length; i++) {
            cookie = cookieArray[i];
            index = cookie.indexOf('=');
            if (index > 0) { //ignore nameless cookies
                name = safeDecodeURIComponent(cookie.substring(0, index));

                if (isUndefined(lastCookies[name])) {
                    lastCookies[name] = safeDecodeURIComponent(cookie.substring(index + 1));
                }
            }
        }
    }
    return lastCookies;
};
})();

Answer 2

using jquery-cookie

I find this library helpful. 3.128 kb of pure convenience.

add script

<script src="/path/to/jquery.cookie.js"></script>

set cookie

$.cookie('name', 'value');

read cookie

$.cookie('name');

Answer 3

Here is an API which was written to smooth over the nasty browser cookie "API"

http://code.google.com/p/cookies/

Answer 4

function getCookie(c_name)
{
    var i,x,y,ARRcookies=document.cookie.split(";");

    for (i=0;i<ARRcookies.length;i++)
    {
        x=ARRcookies[i].substr(0,ARRcookies[i].indexOf("="));
        y=ARRcookies[i].substr(ARRcookies[i].indexOf("=")+1);
        x=x.replace(/^\s+|\s+$/g,"");
        if (x==c_name)
        {
            return unescape(y);
        }
     }
}

Source: W3Schools

Edit: as @zcrar70 noted, the above code is incorrect, please see the following answer Javascript getCookie functions

Answer 5

document.cookie="MYBIGCOOKIE=1";

Your cookies would look like:

"MYBIGCOOKIE=1; PHPSESSID=d76f00dvgrtea8f917f50db8c31cce9"

first of all read all cookies:

var read_cookies = document.cookie;

then split all cookies with ";":

var split_read_cookie = read_cookies.split(";");

then use for loop to read each value. Into loop each value split again with "=":

for (i=0;i<split_read_cookie.length;i++){
    var value=split_read_cookie[i];
    value=value.split("=");
    if(value[0]=="MYBIGCOOKIE" && value[1]=="1"){
        alert('it is 1');
    }
}