Manage Cookies with JS

cookie.js

function createCookie(name,value,days) {
    var expires = '';
    if (days) {
        var date = new Date();
	date.setTime(date.getTime()+(days*24*60*60*1000));
        expires = date.toGMTString();
    } else {
       expires = '';
    }
    
    document.cookie = name+"="+value+expires+"; path=/";
}

function readCookie(name) {
    var nameEQ = name + "=";
    var ca = document.cookie.split(';');
    for (var i=0; i < ca.length; i++) {
        var c = ca[i];
	while (c.charAt(0)==' ') c = c.substring(1,c.length);
	if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
    }
    return null;
}

function eraseCookie(name) {
    createCookie(name,"",-1);
}