Question

Let’s say I have ‘Customer’ table in SQL DB and I’m using Entity Framework.

Now, for instance, in Controller or ViewModel I retrieve the customer by var customer = Page.Current.Customer when it’s code is:

public class Page
{
     ...
     // Customer is EntityObject that created by Entity Framework
     public Customer Customer
     {
        get
        {
                return (new ContextEntity()).Customers.First();
        }
     } 
}

My question:

Should I refer to Entity Object class(Customer) as DAL and create CustomerWrapper or I can use it in other code of my application?

I mean, is it correct that Page.Current.Customer will return Customer Entity or I should use Customer Entity as DAL and Page.Current.Customer should return custom Customer, some kind of CustomWrapper?

In one hand if will decided to change Customer table name to site_Customer(in SQL DB) I’ll refresh the EntityModel and will only change the code in the Page class to

public class Page
    {
         ...
         // Customer is EntityObject that created by Entity Framework
         public Customer Customer
         {
            get
            {
                    return (new ContextEntity()).site_Customers.First();
            }
         } 
    }

But in the other hand I’ll have Customer Entity + WrapperCustomer

What is better?

Answer 1

That all depends on the level of abstraction you want to use in your application and needs of presentation layer. Both approaches are possible.

Your code is probably already tightly coupled to Entity Framework (EntityObject is EF type) and it is also not very well testable (Page.Current is probably static) so discussion about some more advanced architecture approaches and separation of concerns is not needed.

Few observations from your code:

• Context is Disposable!!!
• Renaming anything in your database should not modify your class names. That is the responsibility of EF mapping (EDMX) to correctly map entities to new database names.