Вот пример реализации, которая сделает этот процесс бесшовным (Заимствовано из 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;
};
})();