public HttpResponseMessage AddMaintenanceInfo(ProductInfoOperateDTO dto) { ResultDTO <object> resultdto = new ResultDTO <object>(); try { resultdto.SubmitResult = _IProductServices.AddMaintenanceInfo(dto); } catch (Exception ex) { resultdto.SubmitResult = false; resultdto.Message = ex.Message; } HttpResponseMessage result = new HttpResponseMessage { Content = new StringContent(JsonConvert.SerializeObject(resultdto), System.Text.Encoding.GetEncoding("UTF-8"), "application/json") }; return(result); }