gistfile1.js

function serialize(form) {
    return [].reduce.call(form.elements, function(r, element) {
        return r + (r === '' ? '' : '&') + (function() {

            switch (element.type) {
                case 'checkbox':
                    return name(element.checked);

                case 'radio':
                    return element.checked ? name(element.value) : '';

                default:
                    return name(element.value);
            }

            function name(v) {
                return element.name + '=' + encodeURIComponent(v);
            }
        }());
    }, '');
}