private void dataGrid1_PreviewKeyDown(object sender, KeyEventArgs e)
        {
            var Grid = (DataGrid)sender;

            if (e.Key == Key.Delete)
            {
                foreach (var row in Grid.SelectedItems)
                {
                    PositionOfDay PosOfDay = row as PositionOfDay;
                    if (PosOfDay != null)
                    {
                        ActionResult saveRes = Engine.RemoveNoteFromDB(PosOfDay.CurrentHour, PosOfDay.CurrentMinute);
                        if (!saveRes.IsSuccess)
                        {
                            MessageBox.Show(saveRes.ErrorMsg, "Error");
                        }
                    }
                }

                Engine.UpdateOfPositions();
            }
            else
            if (e.Key == Key.Escape)
            {
                PositionOfDay PosOfDay = Grid.SelectedItem as PositionOfDay;
                if (PosOfDay != null)
                {
                    ActionResult saveRes = Engine.RemoveNoteFromDB(PosOfDay.CurrentHour, PosOfDay.CurrentMinute);
                    if (!saveRes.IsSuccess)
                    {
                        MessageBox.Show(saveRes.ErrorMsg, "Error");
                    }

                    if (!string.IsNullOrWhiteSpace(PosOfDay.OldNote))
                    {
                        var fodg = new FieldsOfDataGrid()
                        {
                            Hour   = PosOfDay.OldHour,
                            Minute = PosOfDay.OldMinute,
                            Note   = PosOfDay.OldNote,
                            User   = PosOfDay.OldUser
                        };

                        ActionResult addNoteResult = Engine.AddNoteToDB(fodg);
                        if (!addNoteResult.IsSuccess)
                        {
                            MessageBox.Show(addNoteResult.ErrorMsg, "Error");
                        }
                    }
                    Engine.UpdateOfPositions();
                }
            }
        }
        public WindowOfPositions(PositionOfDay position, CalendarEngine engine)
            : this()
        {
            _PositionOfDay = position;
            DataContext    = _PositionOfDay;

            _CalendarEngine = engine;
            _Date           = _CalendarEngine.Selected_Date;

            tbDate.Text = _Date.ToString().Remove(10) + _Date.ToString(" (dddd)");

            tbUser.Text = _PositionOfDay.CurrentUser;
        }
        public WindowOfPositions(PositionOfDay position, CalendarEngine engine)
            : this()
        {
            _PositionOfDay = position;
            DataContext = _PositionOfDay;

            _CalendarEngine = engine;
            _Date = _CalendarEngine.Selected_Date;

            tbDate.Text = _Date.ToString().Remove(10) + _Date.ToString(" (dddd)");

            tbUser.Text = _PositionOfDay.CurrentUser;
        }