private void bttinhdiem_Click(object sender, EventArgs e)
 {
     if (txtsodiemtungcau.TextLength == 0)
     {
         MessageBox.Show("Nhập số điểm cho từng câu hỏi vào ô.", "Thông báo", MessageBoxButtons.OK, MessageBoxIcon.Warning);
     }
     else
     {
         lbdiem.Text = (float.Parse(txtsodiemtungcau.Text) * Socaudung).ToString();
         INPHIEUDIEM_PUBLIC inphieudiem_public = new INPHIEUDIEM_PUBLIC();
         CAUHOI_PUBLIC      cauhoi_public      = new CAUHOI_PUBLIC();
         DSNOPBAI_PUBLIC    dsnopbai_public    = new DSNOPBAI_PUBLIC();
         dsnopbai_public.MATHISINH    = Mathisinh;
         dsnopbai_public.MADETHI      = MADETHI;
         dsnopbai_public.MAMONHOC     = Mamonhoc;
         cauhoi_public.MAMONHOC       = Mamonhoc;
         cauhoi_public.MADETHI        = MADETHI;
         inphieudiem_public.Monthi    = Tenmonhoc;
         inphieudiem_public.Tongsocau = dg_dscauhoidalam.Rows.Count - 1;
         inphieudiem_public.Socaudung = Socaudung;
         inphieudiem_public.Socausai  = Socausai;
         inphieudiem_public.Tongdiem  = float.Parse(txtsodiemtungcau.Text) * Socaudung;
         inphieudiem_public.MATS      = Mathisinh;
         inphieudiem_public.MAGV      = Magiaovien;
         inphieudiem_public.Madethi   = MADETHI;
         phieudiem_bul.insert_phieudiem(inphieudiem_public);
         dgphieudiem.DataSource = phieudiem_bul.load_phieudiem(inphieudiem_public);
         Thread inphieu = new Thread(new ThreadStart(save_dialog));
         inphieu.ApartmentState = ApartmentState.STA;
         inphieu.IsBackground   = false;
         inphieu.Start();
         btinphieudiem.Enabled    = false;
         txtsodiemtungcau.Enabled = false;
         cauhoi_bul.update_cauhoidachon(cauhoi_public);
         dsnopbai_bul.delete_dsnopbai(dsnopbai_public);
         Thread tat = new Thread(tatungdung);
         tat.IsBackground = false;
         tat.Start();
     }
 }
        private void PHIEUCHAMDIEM_Load(object sender, EventArgs e)
        {
            dg_thisinh.Hide();
            dgphieudiem.Hide();
            THISINH_PUBLIC     thisinh_public   = new THISINH_PUBLIC();
            CAUHOI_PUBLIC      cauhoi_public    = new CAUHOI_PUBLIC();
            INPHIEUDIEM_PUBLIC phieudiem_public = new INPHIEUDIEM_PUBLIC();

            phieudiem_public.MATS       = Mathisinh;
            cauhoi_public.MAMONHOC      = Mamonhoc;
            thisinh_public.MATS         = Mathisinh;
            cauhoi_public.MADETHI       = MADETHI;
            dg_thisinh.DataSource       = thisinh_bul.load_ts_PD(thisinh_public);
            dg_dscauhoidalam.DataSource = cauhoi_bul.load_cauhoidachon(cauhoi_public);
            dgphieudiem.DataSource      = phieudiem_bul.load_phieudiem(phieudiem_public);
            dinhdangluoi();
            dinhdangphieu();
            lbtenmon.Text        = Tenmonhoc;
            lbtongsocau.Text     = (dg_dscauhoidalam.Rows.Count - 1).ToString();
            lbtongsocaudung.Text = Socaudung.ToString();
            lbtongsocausai.Text  = Socausai.ToString();
            lbmade.Text          = MADETHI;
        }