EF: Should entities have business logic?

Question

I was wondering, should the entities have the capability to save changes to the context? Or have business logic that relates to that particular entity? For example:

ActionResult ResetPassword(UserViewModel viewModel)
{
   var user = userCollection.GetUser(viewModel.Username);
   user.ResetPassword();
}

where:

class User : Entity
{
      public string Password{ get; set; }

      public ResetPassword()
      {
           Password = ""
           context.SaveChanges();
      }
}

I find this a bit weird since the entity would have a reference to the context. I am not sure whether this would work either - or whether this is recommended. But I want to work on a domain where I do not have to worry about saving changes, at a higher level etc. How can I accomplish this?

Thanks!

Update

I have updated my example - hope its a bit clearer now :)

score 2 · Answer 1 · answered Aug 17 '12 at 12:40

2

According to Domain-Driven Design domain objects should have behavior.

You should definately read this book:

enter image description here

answered Aug 17 '12 at 12:40

Steven

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in order to achieve domain-driven behaviour, each entity would have to have a reference to the context, as stated in the question. This seems to be fighting against the mvc .net framework. Have you attempted to do this? – Karan Oct 10 '12 at 09:16

score 1 · Answer 2 · answered Aug 17 '12 at 12:18

1

I would keep my Entities as POCO's(Plain Old Class Objects, classes with only properties) and have a Repositary do methods like Insert / Update.

I can keep my Entities in a separate class library and use it in different places ( even in a different project), with a different Repository implementation.

In this Tutorial It is nicely explained, how to do a Repositary & Unit Of Work Patterns on an MVC project which uses Entity Framework

answered Aug 17 '12 at 12:18

Shyju

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That is interesting. See, I had a different idea. I thought the domain objects should have behaviour as @Steven mentioned. And I thought the models were effectively the entities - such as User. Perhaps a better example would be - whether a user can reset a password. I would have thought it would be the User's responsibility rather than a Repository's responsibility. What do you think Shyju / Steve? – Karan Aug 17 '12 at 14:28

score 1 · Answer 3 · answered Aug 17 '12 at 12:18

1

You may want to consider the UnitOfWork pattern between your controller and your entities.

http://martinfowler.com/eaaCatalog/unitOfWork.html

answered Aug 17 '12 at 12:18

podiluska

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EF: Should entities have business logic?

3 Answers3