cascadia

(function ($) {
    $.fn.cascade = function(child) {
        return this.each(function() {
            var c;
            if(child==undefined)
                c=document.getElementById($(this).attr('data-child').replace('#', ''));
            else
                c=child;

            if(c!=undefined){
                var o = [];
                for (var i = 0; i < c.options.length; i++) {
                    var n = {};
                    for (var e = 0; e < c.options[i].attributes.length; e++) {
                        n[c.options[i].attributes[e].name] = c.options[i].attributes[e].nodeValue;
                    }
                    n.html = c.options[i].innerHTML;
                    o.push(n);
                }
                c.items = o;

                var val = $(c).val();

                $(this).change(function () {
                    var data = c.items;

                    var s = '';
                    for (var i = 0; i < data.length; i++) {

                        if (data[i]['data-fk'] == undefined || data[i]['data-fk'] == $(this).val() ||
                                        $(this).val() == $(this).attr('data-default') ||
                                        data[i]['value'] == '' || $(this).val() == '' ||
                                        data[i]['value'] == '-1' || $(this).val() == '-1') {
                            s += '<option';
                            for (v in data[i])
                                if (v != 'html')
                                    s += ' ' + v + '="' + data[i][v] + '"';
                            s += '>' + data[i].html + '</option>';
                        }
                    }
                    c.innerHTML = s;
                    $(c).groupDropdown();
                });
                if($(this).val()!=$(this).find('option:first-child').val())
                    $(this).change();
            }
        });
    };
})(jQuery);