Question

I’m trying to write a custom validation class that validates that an email is not already is use. To do this, I have a method that counts the userprofiles that have the email address in question. Simple enough, but if the user is updating their profile, I need to exclude their profile from the count I mentioned about. So to do that, I have written the following method:

public static bool IsEmailUnique(string email, int userprofileId)
{
    int count = -1;

    using (var db = new TRDataContext())
    {
        count = (from u in db.Userprofiles
                 where u.email == email &&
                       (userprofileId == 0 || u.userprofile_id != userprofileId)
                 select u).Count();
    }

    return count == 0;
}

This works well in the custom validator class for new users as all I need to do is pass a 0 in for the userprofile_id.

public class EmailValidatorAttribute : ValidationAttribute
{
    public override bool IsValid(object value)
    {
        if (value == null)
            return false;

        return Userprofile.IsEmailUnique(value.ToString(), 0);
    }
}

and implemented like this

[DisplayName("Email Address")]
[Required(ErrorMessage = "Required")]
[RegularExpression(EmailRegex, ErrorMessage = "Invalid email address")]
[EmailValidator(ErrorMessage = "Already in use")]
public string email { get; set; }

However, I now need to pass into the EmailValidator the userprofile_id of that current user. I am having a difficult time figuring this one out.

Any help would be greatly appreciated.

Thanks!

Answer 1

I have had a similar issue. Firstly I implemented a ‘CurrentUser’ method in my user repository that looks a little something like this:

        //Gets the current user
        public U_USER CurrentUser()
        {
            return GetUser(HttpContext.Current.User.Identity.Name);
        }

        public U_USER GetUser(string u)
        {
            return (from us in db.U_USER
                    where us.UserName == u
                    select us).FirstOrDefault();
        }

You can then use this to get the id from inside your validation attribute in a manner similar to the below:

public class EmailValidatorAttribute : ValidationAttribute
{
    public override bool IsValid(object value)
    {
        using(UserRepository ur = new UserRepository())
        {
           if (value == null)
               return false;

           var user = ur.CurrentUser();
           return Userprofile.IsEmailUnique(value.ToString(), user.userprofile_id);
        }
    }
}