private void BtnChange(object sender, RoutedEventArgs e)
        {
            if (DGridFurniture.SelectedItem == null)
            {
                MessageBox.Show("Выберите запись");
                return;
            }
            var std = DGridFurniture.SelectedItem as Furniture;

            AddFurniture fur = new AddFurniture(std);

            fur.Visibility = Visibility.Visible;
            this.Close();
        }
 private void AddFurniture(object sender, RoutedEventArgs e)
 {
     WorkFurniture.AddFurniture fur = new AddFurniture(null);
     fur.Visibility = Visibility.Visible;
     this.Close();
 }