DotNet を使用した Windows SystemEvents コールバックの登録

--First we need the SystemEvents DotNet Class:
c = dotNetClass "Microsoft.Win32.SystemEvents"
-->dotNetClass:Microsoft.Win32.SystemEvents
--Then we get a list of all available events:
showevents c
-->[static] DisplaySettingsChanged <System.Object>sender <System.EventArgs>e = ( ... )
-->[static] DisplaySettingsChanging <System.Object>sender <System.EventArgs>e = ( ... )
-->[static] EventsThreadShutdown <System.Object>sender <System.EventArgs>e = ( ... ) 
-->[static] InstalledFontsChanged <System.Object>sender <System.EventArgs>e = ( ... )
-->[static] LowMemory <System.Object>sender <System.EventArgs>e = ( ... )
-->[static] PaletteChanged <System.Object>sender <System.EventArgs>e = ( ... )
-->[static] PowerModeChanged <System.Object>sender <Microsoft.Win32.PowerModeChangedEventArgs>e = ( ... )
-->[static] SessionEnded <System.Object>sender <Microsoft.Win32.SessionEndedEventArgs>e = ( ... )
-->[static] SessionEnding <System.Object>sender <Microsoft.Win32.SessionEndingEventArgs>e = ( ... )
-->[static] SessionSwitch <System.Object>sender <Microsoft.Win32.SessionSwitchEventArgs>e = ( ... )
-->[static] TimeChanged <System.Object>sender <System.EventArgs>e = ( ... )
-->[static] TimerElapsed <System.Object>sender <Microsoft.Win32.TimerElapsedEventArgs>e = ( ... )
-->[static] UserPreferenceChanged <System.Object>sender <Microsoft.Win32.UserPreferenceChangedEventArgs>e = ( ... )
-->[static] UserPreferenceChanging <System.Object>sender <Microsoft.Win32.UserPreferenceChangingEventArgs>e = ( ... )
-->true
--We define a global function to be called by the event handler:
fn TimeChanged a1 a2 = format "TimeChanged callback: % : %\n" a1 a2
-->TimeChanged()
--Finally we add the Event Handler for the event "TimeChanged":
dotnet.addeventhandler c "TimeChanged" TimeChanged
-->OK