Version: 2021.2
public static void LaunchFile (WSA.Folder folder, string relativeFilePath, bool showWarning);


folder Folder type where the file is located.
relativeFilePath Relative file path inside the specified folder.
showWarning Shows user a warning that application will be switched.


Launches the default app associated with specified file.

Note: if the application associated with file is the same as the one performing the launch, Windows won't open a new application, instead it will simply invoke OnActivated event in App.xaml.[cs/cpp] file.