Try

85         private void btnXuatRaExcel_Click(object sender, EventArgs e)
86         {
87             try
88             {
89
90                 Excel.Application objExcelApp = new Excel.Application();
91                 Excel.Workbook objExcelWorkbook = objExcelApp.Workbooks.Add(Excel.XlWBATemplate.xlWBATWorksheet);
92                 Excel.Worksheet objSheet = (Excel.Worksheet)objExcelWorkbook.Worksheets[1];
93                 //objSheet.Cells.Interior.Color.ToString() = 'blue';
94                 objSheet = (Excel.Worksheet)objExcelWorkbook.Sheets[1];
95                 objSheet.Cells.HorizontalAlignment = Excel.Constants.xlCenter;
96                 objSheet.Cells[2, 5] = "BẢNG ĐIỂM CỦA SINH VIÊN";
97                 objSheet.Cells[5, 3] = "Mã Học Phần";
98                 objSheet.Cells[5, 4] = "Mã Nhóm Học Phần";
99                 objSheet.Cells[5, 5] = "Tên Học Phần";
100                 objSheet.Cells[5, 6] = "Điểm Thi";
101                 objSheet.Cells[5, 7] = "Điểm Quá Trình";
102                 objSheet.Cells[5, 8] = "Điểm Xếp Loại";
103                 objSheet.Cells[3, 3] = "Mã Học Kỳ : "+cmbMaHK.SelectedValue.ToString()+"";
104                 objSheet.Cells[4, 3] = "Mã SV : " + txtMaSV.Text + "";
105                 objSheet.Cells[9,10] = "ĐIỂM TỔNG KẾT";
106                 objSheet.Cells[10,10] = "Hệ 10 : "+txtHe10.Text+"";
107                 objSheet.Cells[11,10] = "Hệ 4 : "+txtHe4.Text+"";
108                 for (int i = 0; i < dgvKetQua.Rows.Count ; i++)
109                 {
110                     for (int j = 0; j < dgvKetQua.Columns.GetColumnCount(DataGridViewElementStates.Displayed); j++)
111                     {
112                         objSheet.Cells[i + 6, j + 3] = dgvKetQua.Rows[i].Cells[j].Value.ToString();
113                         objSheet.Columns.AutoFit();
114                     }
115                 }
116                 objExcelApp.Visible = true;
117             }
118             catch (Exception ex)
119             {
120                 MessageBox.Show(ex.Message);
121             }
122         }

77         private void btnXuatRaExcel_Click(object sender, EventArgs e)
78         {
79              try
80             {
81
82                 Excel.Application objExcelApp = new Excel.Application();
83                 Excel.Workbook objExcelWorkbook = objExcelApp.Workbooks.Add(Excel.XlWBATemplate.xlWBATWorksheet);
84                 Excel.Worksheet objSheet = (Excel.Worksheet)objExcelWorkbook.Worksheets[1];
85                 //objSheet.Cells.Interior.Color.ToString() = 'blue';
86                 objSheet = (Excel.Worksheet)objExcelWorkbook.Sheets[1];
87                 objSheet.Cells.HorizontalAlignment = Excel.Constants.xlCenter;
88                 objSheet.Cells[2, 5] = "BẢNG ĐIỂM CỦA LỚP";
89                 objSheet.Cells[3, 3] = "Mã Học Kỳ : "+cmbMaHK.SelectedValue.ToString()+"";
90                 objSheet.Cells[4, 3] = "Mã Lớp : " + cmbMaLop.SelectedValue.ToString() + "";
91                 objSheet.Cells[5, 4] = "Mã Sinh Viên";
92                 objSheet.Cells[5, 5] = "Tên Sinh Viên";
93                 objSheet.Cells[5, 6] = "Điểm Trung Bình";
94                 //select sv.MaSV,TenSV,TrungBinhCuoiKyHe10
95
96                 for (int i = 0; i < dgvKetQua.Rows.Count ; i++)
97                 {
98                     for (int j = 0; j < dgvKetQua.Columns.GetColumnCount(DataGridViewElementStates.Displayed); j++)
99                     {
100                         objSheet.Cells[i + 6, j + 4] = dgvKetQua.Rows[i].Cells[j].Value.ToString();
101                         objSheet.Columns.AutoFit();
102                     }
103                 }
104                 objExcelApp.Visible = true;
105             }
106             catch (Exception ex)
107             {
108                 MessageBox.Show(ex.Message);
109             }
110         }

183         private void button1_Click_1(object sender, EventArgs e)
184         {
185             try
186             {
187                 string sCauA = textBox1.Text;
188                 string sCauB = textBox2.Text;
189                 string sCauC = textBox3.Text;
190                 string sCauD = textBox4.Text;
191                 string sMaCH = textBox5.Text;
192                 string sCauHoi = richTextBox1.Text;
193                 string sCauDung = "";
194                 string sCauDungLuu = "";
195                 string sTrinhDo = comboBox1.Text;
196                 if (richTextBox1.Text.ToString().Trim() == "" || textBox1.Text == "" || textBox2.Text == "" || textBox3.Text == "" || textBox4.Text == "" || (checkBox1.Checked == false && checkBox2.Checked == false && checkBox3.Checked == false && checkBox4.Checked == false))
197                 {
198                     MessageBox.Show("Bạn đã sai làm thao tác", "Thông báo");
199                 }
200                 else
201                 {
202                     if (checkBox1.Checked == true)
203                     {
204                         sCauDung = "A";
205                         sCauDungLuu += sCauDung;
206                     }
207                     if (checkBox2.Checked == true)
208                     {
209                         sCauDung = "B";
210                         sCauDungLuu += sCauDung;
211                     }
212                     if (checkBox3.Checked == true)
213                     {
214                         sCauDung = "C";
215                         sCauDungLuu += sCauDung;
216                     }
217                     if (checkBox4.Checked == true)
218                     {
219                         sCauDung = "D";
220                         sCauDungLuu += sCauDung;
221                     }
222
223                     sqlcmd = new SqlCommand("update dapan set A='" + sCauA + "',B='" + sCauB + "',C='" + sCauC + "',D='" + sCauD + "',dapan='" + sCauDungLuu + "' where mach='" + sMaCH + "'", sqlcon);
224                     sqlcmd.ExecuteNonQuery();
225                     sqlcmd = new SqlCommand("update cauhoi set cauhoi='" + sCauHoi + "', trinhdo='" + sTrinhDo + "' where mach='" + sMaCH + "'", sqlcon);
226                     sqlcmd.ExecuteNonQuery();
227                     LoadDataToListView();
228                     Bandau();
229                 }
230             }
231
232             catch
233             {
234                 MessageBox.Show("Bạn đã sai làm thao tác", "Thông báo");
235             }
236         }

311         private void button4_Click(object sender, EventArgs e)
312         {
313             if (richTextBox1.Text == "" || textBox1.Text == "" || textBox2.Text == "" || textBox3.Text == "" || textBox4.Text == "" || (checkBox1.Checked == false && checkBox2.Checked == false && checkBox3.Checked == false && checkBox4.Checked == false))
314             {
315                 MessageBox.Show("Bạn chưa thêm đầy đủ thông tin", "Thông báo");
316             }
317             else
318             {
319                 try
320                 {
321
322                     string sCauA = textBox1.Text;
323                     string sCauB = textBox2.Text;
324                     string sCauC = textBox3.Text;
325                     string sCauD = textBox4.Text;
326                     string sMaCH = textBox5.Text;
327                     string sCauHoi = richTextBox1.Text;
328                     string sCauDung = "";
329                     string sCauDungLuu = "";
330                     string sTrinhDo = comboBox1.Text;
331                     if (checkBox1.Checked == true)
332                     {
333                         sCauDung = "A";
334                         sCauDungLuu += sCauDung;
335                     }
336                     if (checkBox2.Checked == true)
337                     {
338                         sCauDung = "B";
339                         sCauDungLuu += sCauDung;
340                     }
341                     if (checkBox3.Checked == true)
342                     {
343                         sCauDung = "C";
344                         sCauDungLuu += sCauDung;
345                     }
346                     if (checkBox4.Checked == true)
347                     {
348                         sCauDung = "D";
349                         sCauDungLuu += sCauDung;
350                     }
351
352                     sqlcmd = new SqlCommand("insert into dapan values('" + sMaCH + "','" + sCauA + "','" + sCauB + "','" + sCauC + "','" + sCauD + "','" + sCauDungLuu + "') ", sqlcon);
353                     sqlcmd.ExecuteNonQuery();
354                     sqlcmd = new SqlCommand("insert into cauhoi values('" + sMaCH + "','" + sCauHoi + "','" + sTrinhDo + "') ", sqlcon);
355                     sqlcmd.ExecuteNonQuery();
356                     LoadDataToListView();
357                     button4.Enabled = false;
358                 }
359                 //roi hen;de bi coi lai thu de cHOAky thu chay thu hen ok
360                 catch
361                 {
362                     MessageBox.Show("Bạn đã thao tác sai");
363                 }
364             }
365         }

30         private void btbatdauthi_Click(object sender, EventArgs e)
31         {
32             try
33             {
34                 if (tbten.Text == "" || tbmathisinh.Text == "")
35                 {
36                     MessageBox.Show("Bạn phải điền đầy đủ thông tin");
37                 }
38                 else
39                 {
40                     string TenThSinh = tbten.Text;
41                     string MaThiSinh = tbmathisinh.Text;
42                     string strSQL = "insert THISINHTHI values('" + MaThiSinh + "','" + TenThSinh + "')";
43                     SqlCommand ObjCmd = new SqlCommand(strSQL, ObjCon);
44                     ObjCmd.ExecuteNonQuery();
45                     if (MessageBox.Show("Bạn có chắc chắn thi không ?", "Thông báo", MessageBoxButtons.YesNo, MessageBoxIcon.Warning) == DialogResult.Yes)
46                     {
47
48                         string dienten = this.tbten.Text;//chuyen thong tin sang form thithat
49                         string dienma = this.tbmathisinh.Text;
50                         frmThiThat thithat = new frmThiThat(dienten, dienma);
51                         thithat.ShowDialog();
52                         this.Close();
53
54
55                     }
56
57                 }
58             }
59             catch
60             {
61                 MessageBox.Show("Mã thí sinh trùng", "Thông báo", MessageBoxButtons.OK, MessageBoxIcon.Warning);
62             }
63
64     }

66         private void btLog_Click(object sender, EventArgs e)
67         {
68             try
69             {
70                 if (txtdangnhap.Text == "" || txtmatkhau.Text == "")
71                 {
72                     MessageBox.Show("Bạn chưa điền đầy đủ thông tin", "Có lỗi xảy ra!");
73                     txtdangnhap.Focus();
74                     return;
75                 }
76                     if(txtdangnhap.Text=="admin" && txtmatkhau.Text=="admin")
77                     {
78                         if (MessageBox.Show("Chào mừng bạn đã đến với mục quản lý dành cho giáo viên", "Thông báo", MessageBoxButtons.OK) == DialogResult.OK)
79                         {
80                             this.Hide();
81                             frmQuanLy_Admin admin = new frmQuanLy_Admin();
82                             admin.ShowDialog();
83
84                         }
85
86                     }
87                 else
88                 {
89                     SqlConnection con = new SqlConnection("server=.\\SQLEXPRESS;database=QL_Thitracnghiem;integrated security=true");
90                     con.Open();
91                     SqlCommand cmd = new SqlCommand("Select MatKhau from THISINH where TenDangNhap ='" + txtdangnhap.Text + "'", con);
92                     SqlDataReader reader = cmd.ExecuteReader();
93                     reader.Read();
94                     if (txtmatkhau.Text == reader.GetValue(0).ToString())
95                     {
96                         MessageBox.Show("Bạn đã đăng nhập thành công!", "Thành công");
97                         reader.Close();
98                         con.Close();
99                         this.Close();
100                         frmLuaChon frmChon = new frmLuaChon();
101                         frmChon.ShowDialog();
102                         this.Hide();
103
104                     }
105                     else
106                     {
107                         MessageBox.Show("Sai Mật Khẩu");
108                         txtmatkhau.Focus();
109                     }
110                     reader.Close();
111                     con.Close();
112                 }
113
114             }
115
116             catch (Exception)
117             {
118
119                 MessageBox.Show("Tên đăng nhập và mật khẩu không hợp lệ","Có lỗi xảy ra");
120                 txtdangnhap.Focus();
121
122             }
123         }

67         private void btnthem_Click(object sender, EventArgs e)
68         {
69             try
70             {
71             string mats = textBox1.Text;
72             string hoten = textBox2.Text;
73             string ngaysinh = textBox3.Text;
74             string gioitinh = textBox4.Text;
75             string quequan = textBox5.Text;
76             string sodt = textBox6.Text;
77             string email = textBox7.Text;
78
79             string strSQL = "insert SINHVIEN values('" + mats + "','" + hoten + "','" + ngaysinh + "','" + gioitinh + "','" + quequan + "','" + sodt + "','" + email + "')";
80             sqlcmd = new SqlCommand(strSQL, sqlcon);
81             sqlcmd.ExecuteNonQuery();
82             MessageBox.Show("B?n dã dang ký thành công");
83             load();
84             }
85                 catch
86             {
87                 MessageBox.Show("Trùng mã sinh viên !!!");
88                 }
89
90         }

97         private void btnsua_Click(object sender, EventArgs e)
98         {
99             try
100             {
101                 string mats = textBox1.Text;
102                 string hoten = textBox2.Text;
103                 string ngaysinh = textBox3.Text;
104                 string gioitinh = textBox4.Text;
105                 string quequan = textBox5.Text;
106                 string sodt = textBox6.Text;
107                 string email = textBox7.Text;
108                 sqlcmd = new SqlCommand("update sinhvien set mats='" + mats + "',hoten='" + hoten + "',ngaysinh='" + ngaysinh + "',gioitinh='" + gioitinh + "',quequan='" + quequan + "',sodienthoai='" + sodt + "',email'" + email + "' ", sqlcon);
109                 sqlcmd.ExecuteNonQuery();
110
111                 load();
112             }
113             catch
114             {
115                 MessageBox.Show("Loi");
116             }
117         }

34         void Load_DeThiThat()
35         {
36             try
37             {
38                 SqlConnection cnn = new SqlConnection("server=.\\SQLEXPRESS;database=QL_Thitracnghiem;integrated security =true");
39                 SqlDataAdapter da = new SqlDataAdapter("select cauhoi.mach,cauhoi,a,b,c,d ,dapan from cauhoi,DAPAN where cauhoi.mach=DAPAN.mach", cnn);
40                 DataTable BangQuestion = new DataTable();
41                 da.Fill(BangQuestion);
42                 TaoBangRandomCauHoi(BangQuestion);
43             }
44             catch (Exception ex)
45             { MessageBox.Show(ex.Message); }
46             p = 60;//nhap thoi gian thi
47             s = 60;
48             h = 0;
49         }

50         void TaoBangRandomCauHoi(DataTable BangQuestion)
51         {
52
53             try
54             {
55                 Random Rnd = new Random();
56                 ArrayList ArrQuestion = new ArrayList();
57
58                 ArrQuestion.Clear();
59                 int x, dem = 0;
60                 int SoCauTrongBangGoc = BangQuestion.Rows.Count;
61                 while (dem < SoCauNgauNhien)
62                 {
63                     x = Rnd.Next(0, SoCauTrongBangGoc);
64                     if (!ArrQuestion.Contains(x))
65                     {
66                         ArrQuestion.Add(x);
67                         dem++;
68                     }
69                 }
70                 for (int j = SoCauTrongBangGoc - 1; j >= 0; j--)
71                     if (!ArrQuestion.Contains(j))
72                         BangQuestion.Rows.RemoveAt(j);
73
74                 BangDeThi = BangQuestion;
75                 BangDeThi.Columns.Add("cauhoi,DAPAN");
76
77             }
78             catch (Exception ex)
79             { MessageBox.Show(ex.Message); }
80
81         }