Question

I working on asp.net mvc3 project. I am using autofac for DI.
I have an attribute Say

public class MustBeLoggedInAttribute : ActionFilterAttribute
{
    private IUserContext Context {get;set;}

    public override void OnActionExecuting(ActionExecutingContext filterContext)
    {
         if (!Context.IsLoggedIn)
             filterContext.Result = new RedirectResult("/users/logon");  
         base.OnActionExecuting(filterContext);
    }

}

So I need to inject my dependency IUserContext to this attribute.
How would I achive it. I found codes here and there on actionfiterprovider,
but couldnt find anything complete.

Help will be appreciated.

Regards

Parminder

Answer 1

From Alex Meyer-Gleaves’ write-up on the Autofac wiki: http://code.google.com/p/autofac/wiki/Mvc3Integration#Filter_Attribute_Property_Injection

You need to call the RegisterFilterProvider() extension method:

using Autofac.Integration.Mvc;

var builder = new ContainerBuilder();
builder.RegisterFilterProvider();

This will inject properties into filter attributes as required (as far as I can tell, you don’t need to register the attribute types with Autofac for this to work.)

Hope this helps,

Nick