Replacing methods that use backgroundworker to async / tpl (.NET 4.0)

Question

My questions are many. Since I saw. NET 4.5, I was very impressed. Unfortunately all my projects are .NET 4.0 and I am not thinking about migrating. So I would like to simplify

Answer 1

How about encapsulating the code that is always the same in a reusable component? You could create a Freezable which implements ICommand, exposes a property of Type DoWorkEventHandler and a Result property. On ICommand.Executed, it would create a BackgroundWorker and wire up the delegates for DoWork and Completed, using the value of the DoWorkEventHandler as event handler, and handling Completed in a way that it sets its own Result property to the result returned in the event.

You'd configure the component in XAML, using a converter to bind the DoWorkEventHandler property to a method on the ViewModel (I assume you've got one), and bind your View to the component's Result property, so it gets updated automatically when Result does a change notification.

The advantages of this solution are: it is reusable, and it works with XAML only, so no more glue code in your ViewModel just for handling BackgroundWorkers. If you don't need your background process to report progress, it could even be unaware that it runs on a background thread, so you can decide in the XAML whether you want to call a method synchronously or asynchronously.