Mouse.MouseWheel Attached Event
Occurs when the mouse wheel is rotated.
Assembly: PresentationCore (in PresentationCore.dll)
Focus or mouse capture take precedence over where the mouse pointer is. If you receive this event from a focused or captured element, the mouse pointer might in fact be over another element at the time.
This is an attached event. WPF implements attached events as routed events. Attached events are fundamentally a XAML language concept for referencing events that can be handled on objects that do not define that event, which WPF expands upon by also enabling the event to traverse a route. Attached events do not have a direct handling syntax in code; to attach handlers for a routed event in code, you use a designated Add*Handler method. For details, see Attached Events Overview.