MVC5 website newbie / Annotations on properties of autogenerated modell

Question

i'm new to mvc 5, and I would like to build an asp.net application to interact with an existing database. I'm using VIsual studio 2013 and Entity Framework 6.

I've generated an ADO.net Entity Data Model from an existing database and I'm currently trying to find out the best way to make data validations, to avoid wrong inputs (let's take as example the field Email from entity Users). The right way seems to be to use Annotations on partial classes. But i don't know how to add an annotation (on the new partial class that i created for that) if the original property declaration is on the autogenerated file.

The autogenerated class, looks like:

namespace Test.Models
{
...
    public partial class Users
        {
        public string Email { get; set; }
        }
...
}

Following the idea behind [this post] (Add data annotations to a class generated by entity framework), i'm trying to make a partial class to write the annotations there, like that:

namespace Test.Models
{
    using System.ComponentModel.DataAnnotations;

    [MetadataType(typeof(UsersMetaData))]
    public partial class Users
    {
         [Someanotations]
         public string Email { get; set; }
    }

}

But on the partial class, i get: 1) Error on the line of "[MetadataType(typeof(UsersMetadata))]", saying that UsersMetadata could not be found, and 2) Error on the line where "public string email", saying that the property is already declared (which sounds logic for me).

How should i annotate on the new partial class the property that is declared on the autogenerated model? It is possible to define a Regex to be used on the anotation?

Thanks for your time,

John

i would like to leave the autogenerated classes living to use them — user3425557, Mar 16 '14 at 12:28

score 0 · Accepted Answer · answered Mar 17 '14 at 13:19

You're almost there. UserMetadata is actually another class that you apply the annotations to. I usually put both of these in the same file.

[MetadataType(typeof(UsersMetaData))]
public partial class Users
{

}
class UsersMetaData
{
    [Someanotations]
    public string Email { get; set; }
}

MVC5 website newbie / Annotations on properties of autogenerated modell

1 Answers1