private void addButton_Click(object sender, EventArgs e)
        {
            AirlineInfo airlineInfo = new AirlineInfo(user, "add");

            airlineInfo.Show();
            this.Hide();
        }
 private void airlineDataGridView_CellDoubleClick(object sender, DataGridViewCellEventArgs e)
 {
     if (airlinesDataGridView.Rows[e.RowIndex].Cells[e.ColumnIndex].Value.ToString().Length == 2)//если выбранная ячейка - код авиалинии
     {
         AirlineInfo airlineInfo = new AirlineInfo(user, airlinesDataGridView.Rows[e.RowIndex].Cells[0].Value.ToString(), airlinesDataGridView.Rows[e.RowIndex].Cells[1].Value.ToString(), airlinesDataGridView.Rows[e.RowIndex].Cells[2].Value.ToString(), airlinesDataGridView.Rows[e.RowIndex].Cells[3].Value.ToString(), "update");
         airlineInfo.Show();
         this.Hide();
     }
 }