.net - 当我已经在使用数据注释中的验证器时，如何在创建对象时强制运行方法？

Question

我有一个类产品，我想验证促销字段并根据价值更改价格。我已经在使用数据注释遵循可靠原则的最佳方法是什么？

` 使用系统；使用 System.ComponentModel.DataAnnotations；

命名空间 RefactoringTest.ProductService.Entities { public class Product : BaseEntity { [DisplayFormat(ConvertEmptyStringToNull = false)] [Required(AllowEmptyStrings = false, ErrorMessage = "ProductName is required.")] public string ProductName { get; 放; }

    [Required(AllowEmptyStrings = false, ErrorMessage = "ProductDescription is required.")]
    [DisplayFormat(ConvertEmptyStringToNull = false)]
    public string ProductDescription { get; set; }

    [Range(1, int.MaxValue, ErrorMessage = "Please enter a value bigger than 0")]
    public int Quantity { get; set; }

    [Range(1, int.MaxValue, ErrorMessage = "Please enter a value bigger than 0")]
    public decimal Price { get; set; }

    [Required(AllowEmptyStrings = false, ErrorMessage = "BrandName is required.")]
    [DisplayFormat(ConvertEmptyStringToNull = false)]
    public string BrandName { get; set; }

    public string Promotion { get; set; }

    public ProductBrand ProductBrand { get; set; }

    public int ProductBrandId { get; set; }


    public void CalculatePriceAfterDiscount()
    {
  switch (Promotion)
        {
            case "5PERCENTOFF":
                Price = Price - Price * 0.05m;
            break;
            case "10PERCENTOFF":
                  Price = Price - Price * 0.1m;
            break;
            case "20PERCENTOFF":
                 Price = Price - Price * 0.2m;
            break;
            default:
                if (!string.IsNullOrEmpty(Promotion))
                throw new ArgumentException("Invalid promotion specified");
            break;
        }
        }
    }      
}

}`

还可以在课堂上使用计算价格方法还是应该在服务中使用？