[JS] Pegar cookie

function pegaCookie(name) {
    var prefix = name + "=";
    var namePos = document.cookie.indexOf(prefix);
    if (namePos == -1) return (null);
    var valuePos = namePos + name.length + 1;
    var endPos = document.cookie.indexOf(";", valuePos);
    if (endPos == -1) endPos = document.cookie.length;
    return (unescape(document.cookie.substring(valuePos, endPos).replace(/\+/g, " ")));
};