无法设置在MVC2定制验证属性membernames [英] Unable to set membernames from custom validation attribute in MVC2

问题描述

我已经通过继承ValidationAttribute创建自定义验证属​​性。该属性在类级，因为它需要验证多个属性应用到我的视图模型。

我重写

 保护覆盖的ValidationResult的IsValid（对象的值，ValidationContext validationContext）
 

和返回：

 新的ValidationResult（总是失败，新的List＆LT;串GT; {出生日期}）;
 

在所有的情况下，出生日期是在我的视图模型的一个属性。

当我跑我的应用程序，我可以看到这个击中。 ModelState.IsValid正确设置为false，但是当我检查的ModelState内容，我看到房产DATEOFBIRTH不包含任何错误。相反，我有一个null值，并包含我在验证属性指定的字符串异常空字符串键。

这导致没有错误信息使用ValidationMessageFor时显示在我的UI。如果我使用的ValidationSummary，那么我可以看到错误。这是因为，它不与媒体资源相关联。

看起来好像是忽略了我在验证结果指定的membername的事实。

这是为什么，以及如何解决呢？

为例code的要求：

  [AttributeUsage（AttributeTargets.Class，的AllowMultiple = FALSE，继承= TRUE）]
    公共类ExampleValidationAttribute：ValidationAttribute
    {
        保护覆盖的ValidationResult的IsValid（对象的值，ValidationContext validationContext）
        {
            //注意，我会做多个属性的复杂的验证完成时，所以这就是为什么它是一个类级别属性
            返回新的ValidationResult（总是失败，新的List＆LT;串GT; {出生日期}）;
        }
    }    [ExampleValidation]
    公共类ExampleViewModel
    {
        公共字符串DATEOFBIRTH {搞定;组; }
    }
 

解决方案

我不知道一个简单的方法解决这个问题。这就是为什么我讨厌数据注解的原因之一。做同样与 FluentValidation 将蛋糕和平：

 公共类ExampleViewModelValidator：AbstractValidator＆LT; ExampleViewModel＆GT;
{
    公共ExampleViewModelValidator（）
    {
        RuleFor（X =＆GT; x.EndDate）
            .GreaterThan（X =＆GT; x.StartDate）
            .WithMessage（结束日期必须在开始日期之后）;
    }
}
 

FluentValidation有很大的支持和ASP.NET MVC 集成。

I have created a custom validation attribute by subclassing ValidationAttribute. The attribute is applied to my viewmodel at the class level as it needs to validate more than one property.

I am overriding

protected override ValidationResult IsValid(object value, ValidationContext validationContext)

and returning:

new ValidationResult("Always Fail", new List<string> { "DateOfBirth" }); 

in all cases where DateOfBirth is one of the properties on my view model.

When I run my application, I can see this getting hit. ModelState.IsValid is set to false correctly but when I inspect the ModelState contents, I see that the Property DateOfBirth does NOT contain any errors. Instead I have an empty string Key with a value of null and an exception containing the string I specified in my validation attribute.

This results in no error message being displayed in my UI when using ValidationMessageFor. If I use ValidationSummary, then I can see the error. This is because it is not associated with a property.

It looks as though it is ignoring the fact that I have specified the membername in the validation result.

Why is this and how do I fix it?

EXAMPLE CODE AS REQUESTED:

 [AttributeUsage(AttributeTargets.Class, AllowMultiple = false, Inherited = true)]
    public class ExampleValidationAttribute : ValidationAttribute
    {
        protected override ValidationResult IsValid(object value, ValidationContext validationContext)
        {
            // note that I will be doing complex validation of multiple properties when complete so this is why it is a class level attribute
            return new ValidationResult("Always Fail", new List<string> { "DateOfBirth" });
        }
    }

    [ExampleValidation]
    public class ExampleViewModel
    {
        public string DateOfBirth { get; set; }
    }

解决方案

I am not aware of an easy way fix this behavior. That's one of the reasons why I hate data annotations. Doing the same with FluentValidation would be a peace of cake:

public class ExampleViewModelValidator: AbstractValidator<ExampleViewModel>
{
    public ExampleViewModelValidator()
    {
        RuleFor(x => x.EndDate)
            .GreaterThan(x => x.StartDate)
            .WithMessage("end date must be after start date");
    }
}

FluentValidation has great support and integration with ASP.NET MVC.

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