Async ctp MVC4 and workflows

Question

I have the below code which calls a workflow. I am wondering if I can changed the controller to be asynchronous using the async ctp.

public ActionResult Index()
         


        

Answer 1

Derive from AsyncController instead of Controller.

EDIT: You may also be experiencing a known bug where ASP.NET MVC4 will hang if the action returns a completed Task. You can work around this bug by adding await Task.Yield(); at the top of the action method.

On an unrelated note, this code is more efficient (and shorter, too):

var workflowTask = Task.Factory.FromAsync(invoker.BeginInvoke, invoker.EndInvoke,
    input, userState);