t4mvc : Cannot inherit a controller class which has no default constructor?

Question

I am using T4MVC with MVC2.

I have the following building blocks:

1. A simple entity interface which defines that every POCO entity must have a l

Answer 1

I see the problem, and it comes down to T4MVC not quite doing the right thing when dealing with generic classes. Normally it would generate a default ctor for it in a partial class, but the fact that it's generic is throwing it off.

You should be able to work around simply by adding a default ctor yourself, e.g.

public abstract partial class EntityController<T> : Controller where T : class, IEntity {
    public EntityController() { }

    // etc...
}

Answer 2

I've noticed something very odd:

I've added the empty constructor to the base class, but without the throw new NotImplementedException(); and it works fine.

But here's the odd thing, when calling the controller if I have an url like /{controller}?params (default action being set to Index in the RouteConfig) the parameterless private controller on the base class is called. But when I have an url like /{controller}/{action}?params then the constructor with parameters is called.

Answer 3

I wanted by controller base class to be abstract and it's constructor protected and parametrized. Got around this issue by adding a blank constructor to ControllerBase that throws a NotImplementedException.

Doesn't quite feel right but it gets the job done. Only issue is when combined with dependency injection the wrong constructor will be called - since it throws an exception the app will bum out.

Code:

public abstract class ControllerBase : Controller
{
    protected object AlwaysSupply { get; private set; }

    public ControllerBase()
    {
        throw new NotImplementedException();
    }

    public ControllerBase(object alwaysSupply)
    {
        AlwaysSupply = alwaysSupply;
    }
}

This will cause T4MVC to generate compilable code. The fault seems to be it always tries to generate a blank (no parameters) constructor for controller classes.

Hope this helps someone.