private void Insertion_Click(object sender, EventArgs e)
        {
            if (HostelAd.Text == "")
            {
                MessageBox.Show("Вы не сможете контролировать постояльцами гостиницы, так как вы к ней не привязаны");
                return;
            }
            ChangeGuests changeGuests = new ChangeGuests();

            if (changeGuests.ShowDialog() == DialogResult.OK)
            {
                string Up_to_Date = "Insert into Guests (Фамилия, Имя, Отчество, [Дата рождения], Пол, [Номер телефона], [Паспортные данные], ID, Гостиница) Values (" +
                                    "'" + changeGuests.Familia.Text + "'," +
                                    "'" + changeGuests.Imya.Text + "'," +
                                    "'" + changeGuests.Otchestvo.Text + "'," +
                                    "'" + changeGuests.WasBorn.Text + "'," +
                                    "'" + changeGuests.Floor.Text + "'," +
                                    "'" + changeGuests.Number.Text + "'," +
                                    "'" + changeGuests.Pachport.Text + "'," +
                                    (GridGuests.Rows.Count + 1) + "," +
                                    HostelAd.Text + ")";

                OleDbConnection sql_conn = new OleDbConnection(ConnectionString);
                OleDbCommand    sql_comm = new OleDbCommand(Up_to_Date, sql_conn);

                sql_conn.Open();
                sql_comm.ExecuteNonQuery();
                sql_conn.Close();
                ShowGuests();
                changeGuests.Close();
            }
        }
        private void Change_Click(object sender, EventArgs e)
        {
            if (HostelAd.Text == "")
            {
                MessageBox.Show("Вы не сможете контролировать постояльцами гостиницы, так как вы к ней не привязаны");
                return;
            }
            ChangeGuests changeGuests = new ChangeGuests();
            int          index        = GridGuests.CurrentRow.Index;
            int          Id           = (int)GridGuests[9, index].Value;

            changeGuests.Familia.Text   = Convert.ToString(GridGuests[1, index].Value);
            changeGuests.Imya.Text      = Convert.ToString(GridGuests[2, index].Value);
            changeGuests.Otchestvo.Text = Convert.ToString(GridGuests[3, index].Value);
            changeGuests.WasBorn.Text   = GridGuests[4, index].Value.ToString();
            changeGuests.Floor.Text     = GridGuests[5, index].Value.ToString();
            changeGuests.Number.Text    = GridGuests[6, index].Value.ToString();
            changeGuests.Pachport.Text  = GridGuests[7, index].Value.ToString();

            if (changeGuests.ShowDialog() == DialogResult.OK)
            {
                string Up_to_Date = "UPDATE Guests SET " +
                                    "Фамилия='" + changeGuests.Familia.Text + "'," +
                                    "Имя='" + changeGuests.Imya.Text + "'," +
                                    "Отчество='" + changeGuests.Otchestvo.Text + "'," +
                                    "[Дата рождения]='" + changeGuests.WasBorn.Text + "'," +
                                    "Пол='" + changeGuests.Floor.Text + "'," +
                                    "[Номер телефона]='" + changeGuests.Number.Text + "'," +
                                    "[Паспортные данные]='" + changeGuests.Pachport.Text + "'" +
                                    " Where ID=" + Id + " And Гостиница=" + HostelAd.Text;

                OleDbConnection sql_conn = new OleDbConnection(ConnectionString);
                OleDbCommand    sql_comm = new OleDbCommand(Up_to_Date, sql_conn);

                sql_conn.Open();
                sql_comm.ExecuteNonQuery();
                sql_conn.Close();
                ShowGuests();
                changeGuests.Close();
            }
        }