}   // Update dataGrid net and gross price value after enter new quantity value

        private void Button_chose_Client_Click(object sender, EventArgs e)
        {
            try
            {
                using (zlecenieEntities db = new zlecenieEntities())
                {
                    kontrahent k = new kontrahent();
                    Window_Choice_Client_For_Offer window_Choice_Client = new Window_Choice_Client_For_Offer(k);
                    window_Choice_Client.ShowDialog();
                    client_id = k.ID;
                    k         = db.kontrahent.Find(k.ID);
                    adres a = new adres();
                    a = db.adres.Find(k.Adres);
                    textBox_Offer_Name.Text        = k.Imie.ToString();
                    textBox_Offer_LastName.Text    = k.Nazwisko.ToString();
                    textBox_Offer_CompanyName.Text = k.Nazwa_Firmy.ToString();
                }
            }
            catch
            {
            }
        } // Add information about Client to Offer Form
        }   // Update dataGrid net and gross price value after enter new quantity value

        private void Button_chose_Client_Click(object sender, EventArgs e)
        {
            using (zlecenieEntities db = new zlecenieEntities())
            {
                kontrahent k = new kontrahent();
                Window_Choice_Client_For_Offer window_Choice_Client = new Window_Choice_Client_For_Offer(k);
                window_Choice_Client.ShowDialog();
                client_id = k.ID;
                k         = db.kontrahent.Find(k.ID);
                adres a = new adres();
                a = db.adres.Find(k.Adres);
                textBox_Offer_Name.Text        = k.Imie.ToString();
                textBox_Offer_LastName.Text    = k.Nazwisko.ToString();
                textBox_Offer_CompanyName.Text = k.Nazwa_Firmy.ToString();
                textBox_Town_Name.Text         = a.Miasto.ToString();
                textBox_Post_Code_1.Text       = a.Kod_pocztowy.ToString().Remove(2, 3);
                textBox_Post_Code_2.Text       = a.Kod_pocztowy.ToString().Remove(0, 2);
                textBox_Street_Name.Text       = a.Nazwa_ulicy.ToString();
                textBox_Building_Number.Text   = a.Numer_budynku.ToString();
                textBox_Home_Number.Text       = a.Numer_mieszkania.ToString();
                textBox_Country_ID.Text        = a.Państwo.ToString();
            }
        } // Add information about Client to Offer Form