function filterHandler(FilterNaam) {
    var form_naam   = 'form_'+FilterNaam;
    var filter_naam = 'filter_'+FilterNaam;
    var url = document.forms[form_naam].elements[filter_naam].options[document.forms[form_naam].elements[filter_naam].selectedIndex].id;
    location = url;
    // url != 0 ? location = url : null;
}
function detailMap(url, urlname, window_width, window_height, scrollbars) {
        var windowprops = "toolbar=no,location=no,directories=no,status=no," +
        "menubar=no,scrollbars="+scrollbars+",resizable=yes,width="+window_width+",height="+window_height;
        window.open (url, urlname, windowprops);
}