https://learn.microsoft.com/en-us/dotnet/api/system.windows.data.datachangedeventmanager?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-10.0
DataChangedEventManager Class (System.Windows.Data) | Microsoft Learn
Provides a WeakEventManager implementation so that you can use the "weak event listener" pattern to attach listeners for the DataChanged event.
class systemwindowsdatamicrosoftlearn