具有数据注释的类级自定义验证ASP MVC

Question

我有以下属性

[AttributeUsage(AttributeTargets.Class, AllowMultiple = false, Inherited = true)]
public class EnsureDeliveryRegistered: ValidationAttribute
{
    public EnsureDeliveryRegistered() { }

    public override bool IsValid(object value)
    {
        return value != null &&
        value is DeliveryViewModel &&
        IntranetOnlineForms.Util.Util.GetDeliveryCount((DeliveryViewModel)value) > 0;
    }
}

适用于以下课程

[EnsureDeliveryRegistered(ErrorMessage = "Defined delivery date(s) result in 0 deliveries to register. Make sure you have the right date; if delivery is a recurring one make sure selected dates and days of week / period will match at least one delivery.")]
    public class DeliveryViewModel
{ //class here }

我的页面视图模型中有这种类型的属性

public class RegisterDeliveryPage
{
    public RegisterDeliveryPage()
    {
        Delivery = new DeliveryViewModel();         
    }

    [Required]
    public DeliveryViewModel Delivery { get; set; }

    //the rest of the code
}

当我提交页面时，会发布整个RegisterDeliveryPage模型

[Route("register")]
    [HttpPost]
    public ActionResult RegisterNewDelivery(RegisterDeliveryPage model)
    {
        try
        {
            if (ModelState.IsValid)
            {
                //todo
            }

            return View("Register", model);
        }
        catch (Exception exc)
        {

        }
    }

在我检查ModelState之后，我可以看到有一个带有注释属性中指定的错误消息的“Delivery”键，但是当我想在视图中显示它时，它没有显示出来。

@Html.ValidationMessage("Delivery")

我在另一个属性中有相同的设置，并且真的不知道这里出了什么问题。