json javascriptserializer length error

        protected override JsonResult Json(object data, string contentType, System.Text.Encoding contentEncoding, JsonRequestBehavior behavior)
        {
            return new JsonResult()
            {
                Data = data,
                ContentType = contentType,
                ContentEncoding = contentEncoding,
                JsonRequestBehavior = behavior,
                MaxJsonLength = Int32.MaxValue
            };
        }

json

var res = (YourClass)Newtonsoft.Json.JsonConvert.DeserializeObject(s, typeof(YourClass));

string jsonString = Newtonsoft.Json.JsonConvert.SerializeObject(o);