为什么即使需要，电话数据注释也无法正常工作？

Question

I've got the [Phone] data annotation defined on a property in my view model:

public class ContactModel : BaseModel
{
    [Required(ErrorMessage = "Please enter your first and last name.")]
    [MaxLength(256, ErrorMessage = "Your name is too long, the maximum is 256 character.")]
    public string Name { get; set; }

    [Required(ErrorMessage = "Please enter your email address.")]
    [EmailAddress(ErrorMessage = "Please enter a valid email address.")]
    [MaxLength(256, ErrorMessage = "Your email address is too long, the maximum is 256 character.")]
    [Display(Name = "Email Address")]
    public string Email { get; set; }

    [Phone(ErrorMessage = "Please enter a valid phone number.")]
    [Display(Name = "Phone Number")]
    public string Phone { get; set; }

    [Required(ErrorMessage = "Please enter your comments or request.")]
    [Display(Name = "Comments or Request")]
    public string Comments { get; set; }
}

but it doesn't validate the format like the [Email] annotation does; even when [Required] . For example, if I enter the text 123 the ModelState.IsValid is still true because that attribute isn't validating the input. To add insult to injury, nothing is happening client-side like it does with the email address. If I enter an invalid email address I actually get the JavaScript validation - as expected.

What's going on?

I'm using Mvc 5.1.0.0 so I've updated to the latest version to ensure it wasn't version specific.

Answer 1

It does, in fact, validate. The problem is that 123 is a valid phone number, somewhere... If you try entering letters, you will notice that validation fails. But, if you enter (123) 234-2342 it succeeds...

This is because it has to work for phone numbers all over the world. It even has to work for internal extensions (which could easily be 2, 3, 4 or 5 digits long). Specifically, if you go here:

http://referencesource.microsoft.com/#System.ComponentModel.DataAnnotations/DataAnnotations/PhoneAttribute.cs

You will see that the regex allows pretty much any numbers. If you want a US Specific Phone validation, then you should probably just use the regex attribute, or develop your own USPhoneAttribute based on this one.