private void putPriceToDatabase(object sender, RoutedEventArgs e)
        {
            string nameofpaper  = comboBox.Text.ToString();
            int    priceofpaper = Convert.ToInt32(textBoxcompaperPrice.Text);

            MessageBox.Show(nameofpaper + "\n" + priceofpaper + "\n" + todayDate + "\n" + todayTime);

            RateTable actual = new RateTable();

            actual.NameOfpaper = nameofpaper;
            actual.Price       = priceofpaper;
            actual.DateOf      = todayDate;
            actual.TimeOf      = todayTime;
            DB.RateTable.Add(actual);
            DB.SaveChanges();
            dataGridRate.ItemsSource = DB.RateTable.ToList();
        }
        private void deletePrice(object sender, RoutedEventArgs e)
        {
            int id = 0;

            try
            {
                id = (dataGridRate.SelectedItem as RateTable).Id;
                RateTable torlendo = new RateTable();
                torlendo = DB.RateTable.Where(d => d.Id == id).First();
                DB.RateTable.Remove(torlendo);
                DB.SaveChanges();
                dataGridRate.ItemsSource = DB.RateTable.ToList();
            }
            catch
            {
                MessageBox.Show("Hiba, jelölje ki a torolni kivánt sort.");
            }
        }