c# - 使用数据注释进行验证不起作用

Question

我正在开发一个带有客户购买模型的 REST API。我已经应用了一些验证，但我看到对十进制类型的属性的验证不起作用，但是，对字符串类型的属性的验证成功工作。
我的行为是如果不添加属性，例如，总计，不应用验证，并且此属性采用十进制类型的默认值，即 0.0
也就是说，我有以下模型:

public class CustomerPurchase : BaseEntity
    {
        [Required(ErrorMessage = "PurchaseFolioRequired")]
        public string Folio { get; set; }

        [Required(ErrorMessage = "PurchaseIvaRequired")]
[Range(typeof(Decimal), "0", "1000000000000000000", ErrorMessage = "PurchaseInvalidVat")]
        public decimal Iva { get; set; }

        [Required(ErrorMessage = "PurchaseSubtotalRequired")]
[Range(typeof(Decimal), "0", "1000000000000000000", ErrorMessage = "PurchaseInvalidSubtotal")]
        public decimal Subtotal { get; set; }

        [Required(ErrorMessage = "PurchaseTotalRequired")]
[Range(typeof(Decimal), "0", "1000000000000000000", ErrorMessage = "PurchaseInvalidTotal")]
        public decimal Total { get; set; }

        [Required(ErrorMessage = "PurchaseTotalLettersRequired")]
        public string TotalLetters { get; set; }

        [Required(ErrorMessage = "PurchaseEmployeeRequired")]
        [BsonRepresentation(BsonType.ObjectId)]
        public string UserId { get; set; }

        [Required(ErrorMessage = "PurchaseProductRequired")]
        [MinLength(1, ErrorMessage = "PurchaseProductRequired")]
        public ProductSold[] Products { get; set; }

        [Required(ErrorMessage = "PurchasePaymentRequired")]
        [MinLength(1, ErrorMessage = "PurchasePaymentRequired")]
        public Payment[] Payments { get; set; }

        [Required(ErrorMessage = "PurchaseClientRequired")]
        public Client Client { get; set; }
    }

这个应用程序是错误的？，或者有一种方法可以严格应用这个验证。
谢谢阅读

Answer 1

decimal是 value type ，所以它总是有一个默认值 - 0在这种情况下，它总是通过您的验证。所以你可以制作它们 nullable :

public class CustomerPurchase : BaseEntity
{
    ....
    [Required(ErrorMessage = "PurchaseIvaRequired")]
    [Range(typeof(Decimal), "0", "1000000000000000000", ErrorMessage = "PurchaseInvalidVat")]
    public decimal? Iva { get; set; }
    ...
}

Docs为 RequiredAttribute也很清楚:

The RequiredAttribute attribute specifies that when a field on a form is validated, the field must contain a value. A validation exception is raised if the property is null, contains an empty string (""), or contains only white-space characters.