Assembly: PresentationCore (in PresentationCore.dll)
Unlike IsMouseOver, this property is only true if the mouse pointer is over the literal element—as it is for a hit test. If the mouse pointer is instead over a child element, in particular over elements that are part of an element's deeper template and compositing, this property will be false. Unless you know how a control is composited (for example, you use this property in a custom control template for a control that you define), this property might return unexpected results. For most scenarios where you are not authoring controls, use IsMouseOver instead.
If the mouse is captured by this element, and this property is true at time of capture, this property will continue to return true until mouse capture is lost and the pointer is not over its bounds.
Available since 3.0