public Result Add(BookModel model) { try { if (_bookRepository.EntityQuery().Any(p => p.Name.ToUpper() == model.Name.ToUpper().Trim())) { return(new ErrorResult("Product with the same name exists!")); } double unitPrice; if (!double.TryParse(model.UnitPriceText.Trim().Replace(",", "."), NumberStyles.Any, CultureInfo.InvariantCulture, out unitPrice)) { return(new ErrorResult("Unit price must be a decimal number!")); } model.UnitPrice = unitPrice; var entity = new Book() { CategoryId = model.CategoryId, Description = model.Description?.Trim(), Name = model.Name.Trim(), StockAmount = model.StockAmount, UnitPrice = model.UnitPrice }; _bookRepository.Add(entity); return(new SuccessResult()); } catch (Exception exc) { return(new ExceptionResult(exc)); } }