jquery获取form表单中的数据

           <form>

                <input name="username" type="text"/>

                <input name="password" type="password"/>

                <input id="subbtn" type="button" value="submit">

            </form>

             $("#subbtn").click(function(){

                    var data = {};

            var t = $('form').serializeArray();
            $.each(t, function() {
                 data [this.name] = this.value;
            });
            alert(JSON.stringify(data ));

            });