$(document).ready(function(){
    $('.currency-option').change(function(){
        if (window.location.href.match(/[?&]setcurrency=[A-Z]{3}/))
            window.location.href =  window.location.href.replace(/setcurrency=[A-Z]{3}/g,'setcurrency=' + $(this).val());
        else {
            if (window.location.href.match(/[?]/))
                window.location.href += '&setcurrency=' + $(this).val();
            else
                window.location.href += '?setcurrency=' + $(this).val();
        }
    });
});