/// <summary> /// Handles changes to the StartAngle property. /// </summary> /// <param name="d">SprocketControl</param> /// <param name="e">DependencyProperty changed event arguments</param> private static void OnStartAngleChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) { SprocketControl sprocket = (SprocketControl)d; double oldStartAngle = (double)e.OldValue; double newStartAngle = sprocket.StartAngle; sprocket.OnStartAngleChanged(oldStartAngle, newStartAngle); }