/// <summary>
        /// Removes a handler from the attached QueryContinueDrag event.
        /// </summary>
        /// <param name="element">The DependencyObject to attach an event handler for.</param>
        /// <param name="handler">The event handler.</param>
        internal static void RemoveQueryContinueDragHandler(DependencyObject element, QueryContinueDragEventHandler handler)
        {
            if (element == null)
            {
                throw new ArgumentNullException("element");
            }
            if (handler == null)
            {
                throw new ArgumentNullException("handler");
            }
            ExtendedRoutedEventHandlerCollection <QueryContinueDragEventHandler, QueryContinueDragEventArgs> handlers = element.GetQueryContinueDragHandlers();

            if (handlers != null)
            {
                handlers.Remove(handler);
            }
        }
        /// <summary>
        /// Removes a handler from the attached GiveFeedback event.
        /// </summary>
        /// <param name="element">The DependencyObject to attach an event handler for.</param>
        /// <param name="handler">The event handler.</param>
        internal static void RemoveGiveFeedbackHandler(DependencyObject element, GiveFeedbackEventHandler handler)
        {
            if (element == null)
            {
                throw new ArgumentNullException("element");
            }
            if (handler == null)
            {
                throw new ArgumentNullException("handler");
            }
            ExtendedRoutedEventHandlerCollection <GiveFeedbackEventHandler, GiveFeedbackEventArgs> handlers = element.GetGiveFeedbackHandlers();

            if (handlers != null)
            {
                handlers.Remove(handler);
            }
        }