Mouse.LostMouseCapture Attached Event
Occurs when an element loses mouse capture.
Assembly: PresentationCore (in PresentationCore.dll)
When an element captures the mouse, it receives mouse input whether or not the cursor is within its borders. T
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.
Because of the bubbling routing, the actual element that lost capture might be a child element, not necessarily the element where the event handler is actually attached. Check the Source in the event arguments to determine the actual element that lost capture.