https://learn.microsoft.com/ru-ru/dotnet/api/system.windows.forms.control.accessibilitynotifyclients?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-10.0
Control.AccessibilityNotifyClients Method (System.Windows.Forms) | Microsoft Learn
Notifies the accessibility client applications of AccessibleEvents.
windows formscontrolmethodsystemmicrosoft