public string Delete(string TenDangNhap, string ChucVu) { if (ChucVu != "Admin") { try { NguoiDung.XoaNguoiDung(TenDangNhap); if (NguoiDung.DSNguoiDungTheoTen(TenDangNhap).Count() == 0) { return("successed"); } else { return("failed"); } } catch { return("failed"); } } else { return("failed"); } }