void Them(HocPhan s)
{
ds.Add(s);
}
public string Xuat(HocPhan hp)
{
this.hp = hp;
return(string.Format("{0}|{1}|{2}|{3}|{4}|{5}|{6}", CanhLe(maSV, 10), CanhLe(MaMH, 10), CanhLe(hp.TenHP, 15), hp.soTC, hp.lT, hp.tH, diem));
}
