private void dgvSinhvien_CellClick(object sender, DataGridViewCellEventArgs e)
        {
            if (dgvSinhvien.CurrentCell.ColumnIndex != 1)
            {
                return;
            }
            currentIDSinhVien = Int32.Parse(dgvSinhvien.CurrentRow.Cells[1].Value.ToString());
            SinhVien sv = SinhVienController.GetSinhVien(currentIDSinhVien);

            txtHoten.Text            = sv.HoTen.Trim();
            txtMssv.Text             = sv.MSSV.Trim();
            dtpNgaySinh.Value        = DateTime.Parse(sv.NgaySinh.ToString());
            txtEmail.Text            = sv.Email.Trim();
            txtSdt.Text              = sv.SDT.Trim();
            cbGioitinh.SelectedIndex = cbGioitinh.FindStringExact(sv.GioiTinh.Trim());
            foreach (Nhom nhomTrongCB in cbNhom.Items)
            {
                if (nhomTrongCB.IDNhom == sv.Nhom.IDNhom)
                {
                    cbNhom.SelectedIndex = cbNhom.Items.IndexOf(nhomTrongCB);
                    return;
                }
            }
        }