Occurs when a control starts transitioning to a different state.
Assembly: PresentationFramework (in PresentationFramework.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml/presentation, http://schemas.microsoft.com/netfx/2007/xaml/presentation
The event occurs when the control begins to transition states. If a VisualTransition is applied to the state change, this event occurs when the transition begins. If a VisualTransition is not applied, this event occurs after the control transitions to the new state, but before the CurrentStateChanged event.
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2