Drag over control to command bahvior

DragOverControlToCommandBehavior.cs

public class DragOverControlToCommandBehavior : CommandBehaviorBase<Control>
    {
        public DragOverControlToCommandBehavior(Control element)
            : base(element)
        {
            element.AllowDrop = true;
            element.DragOver += ElementDragOver;
        }

        private void ElementDragOver(object sender, DragEventArgs e)
        {
            this.ExecuteCommand();
        }
    }


    public class DragOverControlToCommandDependency
    {
        public static readonly DependencyProperty CommandProperty =
            DependencyProperty.RegisterAttached("Command", typeof(ICommand), typeof(DragOverControlToCommandDependency), new PropertyMetadata(OnSetCommandCallback));

        public static readonly DependencyProperty CommandParameterProperty =
            DependencyProperty.RegisterAttached("CommandParameter", typeof(object), typeof(DragOverControlToCommandDependency), new PropertyMetadata(OnSetCommandParameterCallback));

        public static readonly DependencyProperty PatientDragOverControlToCommandBehaviorProperty =
            DependencyProperty.RegisterAttached("DragOverControlToCommandBehavior", typeof(DragOverControlToCommandBehavior), typeof(DragOverControlToCommandDependency), null);


        public static ICommand GetCommand(DependencyObject obj)
        {
            return (ICommand)obj.GetValue(CommandProperty);
        }
        public static void SetCommand(DependencyObject obj, ICommand value)
        {
            obj.SetValue(CommandProperty, value);
        }

        public static object GetCommandParameter(DependencyObject obj)
        {
            return obj.GetValue(CommandParameterProperty);
        }
        public static void SetCommandParameter(DependencyObject obj, object parameter)
        {
            obj.SetValue(CommandParameterProperty, parameter);
        }

        public static DragOverControlToCommandBehavior GetPatientDragOverControlToCommandBehavior(DependencyObject obj)
        {
            return (DragOverControlToCommandBehavior)obj.GetValue(PatientDragOverControlToCommandBehaviorProperty);
        }
        public static void SetPatientDragOverControlToCommandBehavior(DependencyObject obj, DragOverControlToCommandBehavior value)
        {
            obj.SetValue(PatientDragOverControlToCommandBehaviorProperty, value);
        }



        private static void OnSetCommandCallback(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var element = d as Control;
            if (element != null)
            {
                var behavior = GetOrCreateBehavior(element);
                behavior.Command = e.NewValue as ICommand;
            }
        }

        private static void OnSetCommandParameterCallback(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var element = d as Control;
            if (element != null)
            {
                var behavior = GetOrCreateBehavior(element);
                behavior.CommandParameter = e.NewValue;
            }
        }

        private static DragOverControlToCommandBehavior GetOrCreateBehavior(Control element)
        {
            var behavior = element.GetValue(PatientDragOverControlToCommandBehaviorProperty) as DragOverControlToCommandBehavior;
            if (behavior == null)
            {
                behavior = new DragOverControlToCommandBehavior(element);
                element.SetValue(PatientDragOverControlToCommandBehaviorProperty, behavior);
            }

            return behavior;
        }
    }