public ActionResult Activate(long surveyModelId)
        {
            try
            {
                db.ActivateSurvey(!db.FindSurvey(surveyModelId).Active, surveyModelId);

                return(Redirect(Request.UrlReferrer.AbsoluteUri));
            }
            catch (Exception ex)
            {
                Log.Error(ex.Message, ex);
                return(HttpNotFound());
            }
        }