public JsonResult Delete(int?id)
        {
            int result = 0;

            if (id != null)
            {
                result = sliderHelper.DeleteSlider(id.Value);
                if (result > 0)
                {
                    return(Json(new { result }, JsonRequestBehavior.AllowGet));
                }
            }
            return(Json(new { result }, JsonRequestBehavior.AllowGet));
        }