var NameOfCookie = "sidenav";

function write_cookie(cookiename,expiration,writethis) {

var expDate = new Date();
var future = expDate.getTime() + expiration; //24 * 60 * 60 * 1000 -- Milliseconds in 1 day. Multiply by number of days to get expiration date
expDate.setTime(future)
document.cookie = cookiename + "=" + escape(writethis) + "; expires=" + expDate.toGMTString() + ";path=/";
}

function read_cookie() {

var allcookies = parsecookie();

	if (allcookies) {
		var cookie_array = allcookies.split(",");
		var new_allcookies = new Array();
	
		for (var i = 0; i < 1; i++) {
			end_point = cookie_array[i].indexOf('=');
			new_allcookies[i] = cookie_array[i].slice((end_point + 1), cookie_array[i].length);
		}
		return new_allcookies[0];			
	}
}

function parsecookie() {

var cookieholder = document.cookie;

	if (cookieholder.length > 0) { 
		var begin = cookieholder.indexOf(NameOfCookie+"="); 
		if (begin != -1) { 
			begin += NameOfCookie.length+1; 
			var end = cookieholder.indexOf(";", begin);
			if (end == -1) {
				end = cookieholder.length;
			}
			return unescape(cookieholder.substring(begin, end)); 
		}
		else {
			return false;
		}
	}
}