function getQuerystring(key, default_) {
    if (default_ == null) default_ = "";
    key = key.replace(/[\[]/, "\\\[").replace(/[\]]/, "\\\]");
    var regex = new RegExp("[\\?&]" + key + "=([^&#]*)");
    var qs = regex.exec(window.location.href);
    if (qs == null)
        return default_;
    else
        return qs[1];
}

function setCookie(name, value, seconds) {

    if (typeof (seconds) != 'undefined') {
        var date = new Date();
        date.setTime(date.getTime() + (seconds * 1000));
        var expires = "; expires=" + date.toGMTString();
    }
    else {
        var expires = "";
    }

    document.cookie = name + "=" + value + expires + "; path=/";
}

var af = getQuerystring("af");

if (af === "") {

}
else {
    setCookie("affiliate", af, 60 * 60 * 24 * 30);
}