I'm still struggling a bit with OOP concepts and dependency injection so bear with me.

I have generated my Linq2Sql model with a User table and now I would like to be able to send a confirmation email to this user so I created a partial class file for my User object and I felt it was natural to add a SendConfirmationEmail() method to the User class. This method will use a MailService to send the actual email and I would like to use dependency injection to pass in the service so I created a constructor overload on the User object like this

```
public User(IMailService service) : this()
{
    _service = service;
}

```

The SendConfirmationEmail method would look like this

```
public void SendConfirmationEmail()
{
    _service.SendMail(params...);
}

```

I realize this is a kind of poor mans dependency injection and I hope to switch to a dependency injection framework later as I am getting more grips on this. 

The problem for me is that I need to make a reference from my model dll to my service dll which does not seem right and because I am unsure of how nice my linq2sql generated entities plays with Dependency injection frameworks and OOP concepts (I think ninject looks most promising). 

I was hoping someone with a bit more experience than me could tell I'm if I am going in the right direction with this. I know I can make it work but I would like to educate my self in doing it in the correct way in the same step.