ChatterBox.Client.Presentation.Shared.Behaviors.ReturnKeyCloseKeyboardBehavior.OnEnabledPropertyChanged C# (CSharp) Method

        private static void OnEnabledPropertyChanged(DependencyObject dp, DependencyPropertyChangedEventArgs e)
        {
            var element = dp as UIElement;

            if (element == null) return;

            if (e.OldValue != null)
            {
                element.KeyDown += Element_KeyDown;
            }

            if (e.NewValue != null)
            {
                element.KeyDown += Element_KeyDown;
            }
        }