Assembly: PresentationFramework (in PresentationFramework.dll)
The ToolTipOpening event occurs immediately before a tooltip opens. This event does not occur if the tooltip is not defined or if the tooltip content is set to null.
This field registers the behavior of the ToolTipOpening event for classes that use this service. The FrameworkElement and FrameworkContentElement classes both implement the ToolTipService and expose this event through the common language runtime (CLR) accessors FrameworkElement.ToolTipOpening and FrameworkContentElement.ToolTipOpening.
The following example shows how to set an event handler for the FrameworkElement.ToolTipOpening event. In this case, the event handler is actually for FrameworkElement.ToolTipOpening, because the Ellipse where the handler is attached is a derived class of FrameworkElement.
Available since 3.0