private void button3_Click(object sender, EventArgs e)
        {
            PharmacyData            db       = new PharmacyData();
            IQueryable <Medicament> medsList = from b in db.Medicaments
                                               orderby b.Id
                                               select b;
            List <Medicament> medicaments = medsList.ToList();

            foreach (Medicament medicament in medicaments)
            {
                if (medicament.MedName == "Paracetamol")
                {
                    medicament.MedQuantity = medicament.MedQuantity - Data.ParacetamolQuantity;
                }
                if (medicament.MedName == "Algocalmin")
                {
                    medicament.MedQuantity = medicament.MedQuantity - Data.AlgocalminQuantity;
                }
                if (medicament.MedName == "Coldrex")
                {
                    medicament.MedQuantity = medicament.MedQuantity - Data.ColdrexQuantity;
                }
                if (medicament.MedName == "Vitamine")
                {
                    medicament.MedQuantity = medicament.MedQuantity - Data.VitamineQuantity;
                }
            }
            db.SaveChanges();
            Data.ParacetamolQuantity = 0;
            Data.AlgocalminQuantity  = 0;
            Data.ColdrexQuantity     = 0;
            Data.VitamineQuantity    = 0;
            this.Hide();
            Form comanda = new ComandaFinalizata();

            comanda.Show();
        }
        private void registerButton_Click(object sender, EventArgs e)
        {
            /*if (usernameBox.Text != null && passwordBox.Text != null && confirmPasswordBox.Text != null &&!string.IsNullOrWhiteSpace(usernameBox.Text) && !string.IsNullOrWhiteSpace(passwordBox.Text))
             * {
             *  if (passwordBox.Text == confirmPasswordBox.Text && passwordBox.Text != null && !string.IsNullOrWhiteSpace(passwordBox.Text))
             *  {
             *      /*var db = new PharmacyData();
             *      TbUser tbUser = new TbUser();
             *      tbUser.Username = usernameBox.Text;
             *      tbUser.Password = passwordBox.Text;
             *      db.TbUsers.Add(tbUser);
             *      db.SaveChanges();
             *      PharmacyData db = new PharmacyData();
             *      IQueryable<TbUser> tbUsersList = from b in db.TbUsers
             *                                       orderby b.Id
             *                                       select b;
             *      List<TbUser> tbUsers = tbUsersList.ToList();
             *
             *      foreach (TbUser tbUser in tbUsers)
             *      {
             *          if (tbUser.Username == usernameBox.Text && !string.IsNullOrWhiteSpace(usernameBox.Text))
             *          {
             *              if (tbUser.Password == passwordBox.Text && !string.IsNullOrWhiteSpace(passwordBox.Text))
             *              {
             *
             *              }
             *          }
             *      }
             *  }
             * }*/
            bool found = false;

            if (usernameBox.Text != null && passwordBox.Text != null && confirmPasswordBox.Text != null && !string.IsNullOrWhiteSpace(usernameBox.Text) && !string.IsNullOrWhiteSpace(passwordBox.Text))
            {
                PharmacyData        db          = new PharmacyData();
                IQueryable <TbUser> tbUsersList = from b in db.TbUsers
                                                  orderby b.Id
                                                  select b;
                List <TbUser> tbUsers = tbUsersList.ToList();

                foreach (TbUser tbUser in tbUsers)
                {
                    if (tbUser.Username == usernameBox.Text && !string.IsNullOrWhiteSpace(usernameBox.Text))
                    {
                        found = true;
                        MessageBox.Show("User already exists!");
                    }
                }
            }
            if (found == false)
            {
                if (passwordBox.Text == confirmPasswordBox.Text && passwordBox.Text != null && !string.IsNullOrWhiteSpace(passwordBox.Text))
                {
                    var    db     = new PharmacyData();
                    TbUser tbUser = new TbUser();
                    tbUser.Username = usernameBox.Text;
                    tbUser.Password = passwordBox.Text;
                    db.TbUsers.Add(tbUser);
                    db.SaveChanges();
                }
            }
        }