Email model validation with DataAnnotations and DataType

Question

I have following model:

public class FormularModel
{
    [Required]
    public string Position { get; set; }
    [Required]
    [DataType(DataType.EmailAddress)]
    public string Email { get; set; }
    [Required]
    public string Webcode { get; set; }
}

Required validation works fine. But when i try with DataType it doesn't react.

Here is my razor code for the email control:

   @Html.TextBoxFor
          (model => model.Email, 
           new { @style = "width: 175px;", @class = "txtField" }
          ) * 

So, anyone know an answer?

TIA

Strip

Check this Example: codingfusion.com/Post/… – Tenrec

Answer 1

DataType attribute is used for formatting purposes, not for validation.

I suggest you use ASP.NET MVC 3 Futures for email validation.

Sample code:

[Required]
[DataType(DataType.EmailAddress)]
[EmailAddress]
public string Email { get; set; }

---

If you happen to be using .NET Framework 4.5, there's now a built in EmailAddressAttribute that lives in System.ComponentModel.DataAnnotations.EmailAddressAttribute.

Valuable

but it accepts 'something@domain' . i guess i will go with regular expression this time. – Villegas

As we cant give custom error message. Am using this following way instead. [EmailValidation(ErrorMessage = "The Email Address already exists")] [RegularExpression( "^[a-z0-9_\\+-]+(\\.[a-z0-9_\\+-]+)*@[a-z0-9-]+(\\.[a-z0-9]+)*\\.([a-z]{2,4})$" , ErrorMessage = "Invalid email format." )] [Required(ErrorMessage = "Please enter your e-mail address."), StringLength(50)] public string Email { get; set; } – Epithet

That Regex will fail for "ryan.o'[email protected]" – Arthro

Answer 2

I have looked at the source code (reverse engineered by Reflector) and DataType variants are actually not even implemented! (This was for DateType.Date)

So it is not going to work.

I would personally use RegexValidation for email.

---

For clarity, here is the implementation of IsValid in class DataTypeAttribute:

public override bool IsValid(object value)
{
    return true;
}

Submaxillary

hehehe... everything is valid! =) – Valuable

Regex validation of email addresses is a really bad idea; the RFC allows to many weird permutations to make a regex feasible. Even tagged emails, as supported by GMail, usually get rejected as invalid, despite being perfectly valid. (davidcel.is/blog/2012/09/06/… points this out well). programmers.stackexchange.com/questions/78353/… explores the various options, but the only 100% guarantee is to email the address and check for bounces. – Confectionery

Answer 3

I used this regex pattern which will allow some of the newer longer extensions (.mynewsite, etc).

@"^[\w-_]+(\.[\w!#$%'*+\/=?\^`{|}]+)*@((([\-\w]+\.)+[a-zA-Z]{2,20})|(([0-9]{1,3}\.){3}[0-9]{1,3}))$"

Not Valid, among others too:

• email@com
• email-o'[email protected] <-- doesn't like the tick, oh well.

Examples that work:

• [email protected]

EDIT - UPDATE 5/17/2024

From a question below, I use this: I'm using an improved regex value, different from the original one above.

using System.ComponentModel.DataAnnotations;



  public static class RegexPatterns
    {
        public const string Email = @"^[a-zA-Z0-9._\\-]+@[a-zA-Z0-9]+(([\\-]*[a-zA-Z0-9]+)*[.][a-zA-Z0-9]+)+(;[ ]*[a-zA-Z0-9._\\-]+@[a-zA-Z0-9]+(([\\-]*[a-zA-Z0-9]+)*[.][a-zA-Z0-9]+)+)*$";
    }
public class User
{
    [Required]
    [RegularExpression(RegexPatterns.Email, ErrorMessage = "Username can only contain alphanumeric characters.")]
    public string Email{ get; set; }

}

Teakwood

For those implementing Regex format validations. This can impact the performance of your application. – Augury

Can you edit this and show how to implement this regex pattern using DataAnnotations on the original question? I don't know how to add your regex text to DataAnnotations. – Ezar

The regex is complicated, so I use a constant. Here's an improved regex: ^[a-zA-Z0-9._\\-]+@[a-zA-Z0-9]+(([\\-]*[a-zA-Z0-9]+)*[.][a-zA-Z0-9]+)+(;[ ]*[a-zA-Z0-9._\\-]+@[a-zA-Z0-9]+(([\\-]*[a-zA-Z0-9]+)*[.][a-zA-Z0-9]+)+)*$ public static class RegexPatterns { public const string Email = @"Add your regex here$"; } public class User { [Required] [RegularExpression(RegexPatterns.Email, ErrorMessage = "Username can only contain alphanumeric characters.")] public string Email { get; set; } – Teakwood

@Ezar Look up in my response, I edited it to show how to incorporate this into the class. Hope this helps. – Teakwood

Answer 4

I think you need to add at html code one componente Html.ValidationMessageFor. This component shows the validation.

The code may be (using razor):

@Html.TextBoxFor(model => model.Email)
@Html.ValidationMessageFor(model => model.Email)

try it.

Anthrax