How are Async Business Rules run from PropertyHasChanged?

[Greg90277]

Hi all.

Using CSLA 8, Blazor Server.

I'm having a bit of a problem understanding how to move towards a "top-to-bottom" async approach given that so many methods are simple synchronous void methods.

For example - PropertyHasChanged is a simple sync void. In the base class it automatically calls CheckPropertyRules. Again - sync.

So how are we supposed to call Asynchronous business rules from PropertyHasChanged and follow recommended guidance to NEVER use async void for event handlers etc.?

More generally - how can we call any custom Async methods from PropertyHasChanged?

I'd love to hear how people are handling this. Thanks in advance!

Greg

[rockfordlhotka]

This is an ongoing issue - friction between old C# and modern .NET - where the data binding interfaces like INotifyPropertyChanged, etc. predate modern async concepts. There's only so much CSLA can do with this, because we need to honor the .NET interfaces to work as expected with .NET UI frameworks.

Blazor generally doesn't use the older UI framework constructs, but we can't abandon them as long as people continue to use Windows Forms, WPF, Web Forms, MVC, etc. This kind of puts us in a bind (pun intended) in some ways 😉

You use the phrase So how are we supposed to call Asynchronous business rules - which raises an alert in my mind, because you shouldn't be calling rules at all - the CSLA rules engine should be calling the rules on your behalf. You should only care that you don't proceed beyond certain points in your UI workflow until async rules are complete - and there are good async-safe ways to know when that happens.