private void add_Click(object sender, EventArgs e)
 {
     editStudent es = new editStudent(group.SelectedValue, "", "", "", "", "", "");
     es.Show();
 }
        private void upd_Click(object sender, EventArgs e)
        {
            if (dg.CurrentRow != null)
            {
                string id = dg.CurrentRow.Cells[0].Value.ToString();
                string surname = dg.CurrentRow.Cells[1].Value.ToString();
                string name = dg.CurrentRow.Cells[2].Value.ToString();
                string name2 = dg.CurrentRow.Cells[3].Value.ToString();
                string path = dg.CurrentRow.Cells[6].Value.ToString();
                editStudent es = new editStudent(group.SelectedValue, surname, name, name2, "update", id, path);

                es.Show();

            }
            else
            {
                MessageBox.Show("Выберите студента!");
            }
        }