https://learn.microsoft.com/en-us/dotnet/api/system.windows.contentelement.previewmousewheel?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-10.0
ContentElement.PreviewMouseWheel Event (System.Windows) | Microsoft Learn
Occurs when the user rotates the mouse wheel while the mouse pointer is over this element.
event systemwindowsmicrosoftlearn