private void bt_baocao_Click(object sender, EventArgs e)
        {
            //Create a new workbook
            Spire.Xls.Workbook workbook = new Spire.Xls.Workbook();

            //Initialize worksheet
            workbook.CreateEmptySheets(1);
            Spire.Xls.Worksheet sheet = workbook.Worksheets[0];
            string        conString   = @"Data Source=DESKTOP-RGHAECC;Initial Catalog=SucKhoeNhanVien_PNT;Integrated Security=True";
            SqlConnection sqlCon      = new SqlConnection(conString);

            sqlCon.Open();

            SqlDataAdapter da = new SqlDataAdapter("SELECT LichSuBenh.Id_LichSuBenh,NhanVien.MaNV,NhanVien.TenNV,Khoa.TenKhoa,ChucVu.TenChucVu,LichSuBenh.NgayKham,LichSuBenh.PhanLoaiSK,LichSuBenh.BenhKhac from NhanVien, LichSuBenh, Khoa , ChucVu where NhanVien.IdNhanVien = LichSuBenh.IdNhanVien And NhanVien.Khoa = Khoa.IdKhoa And NhanVien.IdChucVu = ChucVu.IdChucVu", sqlCon);

            System.Data.DataTable dtMainSQLData = new System.Data.DataTable();
            da.Fill(dtMainSQLData);
            DataColumnCollection dcCollection = dtMainSQLData.Columns;

            // Export Data into EXCEL Sheet
            Microsoft.Office.Interop.Excel.Application ExcelApp = new Microsoft.Office.Interop.Excel.Application();
            ExcelApp.Application.Workbooks.Add(Type.Missing);
            ExcelApp.Columns.ColumnWidth = 20;

            //Create a new workbook
            // Spire.Xls.Workbook workbook = new Spire.Xls.Workbook();

            //Initialize worksheet
            // workbook.CreateEmptySheets(1);
            //Spire.Xls.Worksheet sheet = workbook.Worksheets[0];

            //Set sheet name
            sheet.Name = "Chart data";

            //Set the grid lines invisible
            sheet.GridLinesVisible = false;

            //Create a chart
            Spire.Xls.Chart chart = sheet.Charts.Add(ExcelChartType.Pie3D);

            //Set region of chart data
            chart.DataRange           = sheet.Range["B2:B5"];
            chart.SeriesDataFromRange = false;

            //Set position of chart
            chart.LeftColumn  = 1;
            chart.TopRow      = 6;
            chart.RightColumn = 9;
            chart.BottomRow   = 25;

            //Chart title
            chart.ChartTitle            = "Sales by year";
            chart.ChartTitleArea.IsBold = true;
            chart.ChartTitleArea.Size   = 12;

            //Initialize the chart series
            Spire.Xls.Charts.ChartSerie cs = chart.Series[0];

            //Chart Labels resource
            cs.CategoryLabels = sheet.Range["A2:A5"];

            //Chart value resource
            cs.Values = sheet.Range["B2:B5"];

            //Set the value visible in the chart
            cs.DataPoints.DefaultDataPoint.DataLabels.HasValue = true;

            //Year
            sheet.Range["A1"].Value = "Year";
            sheet.Range["A2"].Value = "2002";
            sheet.Range["A3"].Value = "2003";
            sheet.Range["A4"].Value = "2004";
            sheet.Range["A5"].Value = "2005";

            //Sales
            sheet.Range["B1"].Value       = "Sales";
            sheet.Range["B2"].NumberValue = 4000;
            sheet.Range["B3"].NumberValue = 6000;
            sheet.Range["B4"].NumberValue = 7000;
            sheet.Range["B5"].NumberValue = 8500;

            //Style
            sheet.Range["A1:B1"].Style.Font.IsBold = true;
            sheet.Range["A2:B2"].Style.KnownColor  = ExcelColors.LightYellow;
            sheet.Range["A3:B3"].Style.KnownColor  = ExcelColors.LightGreen1;
            sheet.Range["A4:B4"].Style.KnownColor  = ExcelColors.LightOrange;
            sheet.Range["A5:B5"].Style.KnownColor  = ExcelColors.LightTurquoise;

            //Border
            sheet.Range["A1:B5"].Style.Borders[BordersLineType.EdgeTop].Color        = Color.FromArgb(0, 0, 128);
            sheet.Range["A1:B5"].Style.Borders[BordersLineType.EdgeTop].LineStyle    = LineStyleType.Thin;
            sheet.Range["A1:B5"].Style.Borders[BordersLineType.EdgeBottom].Color     = Color.FromArgb(0, 0, 128);
            sheet.Range["A1:B5"].Style.Borders[BordersLineType.EdgeBottom].LineStyle = LineStyleType.Thin;
            sheet.Range["A1:B5"].Style.Borders[BordersLineType.EdgeLeft].Color       = Color.FromArgb(0, 0, 128);
            sheet.Range["A1:B5"].Style.Borders[BordersLineType.EdgeLeft].LineStyle   = LineStyleType.Thin;
            sheet.Range["A1:B5"].Style.Borders[BordersLineType.EdgeRight].Color      = Color.FromArgb(0, 0, 128);
            sheet.Range["A1:B5"].Style.Borders[BordersLineType.EdgeRight].LineStyle  = LineStyleType.Thin;

            //Number format
            sheet.Range["B2:C5"].Style.NumberFormat = "\"$\"#,##0";
            chart.PlotArea.Fill.Visible             = false;

            //Save the file
            // workbook.SaveToFile("Sample.xls", ExcelVersion.Version97to2003);

            //Launch the file
            //System.Diagnostics.Process.Start("Sample.xls");



            // ExcelApp.Cells.CopyFromRecordset(objRS);
            for (int i = 1; i < dtMainSQLData.Rows.Count + 2; i++)
            {
                for (int j = 1; j < dtMainSQLData.Columns.Count + 1; j++)
                {
                    if (i == 1)
                    {
                        ExcelApp.Cells[i, j]                     = dcCollection[j - 1].ToString();
                        ExcelApp.Cells[i, j].Font.Bold           = true;
                        ExcelApp.Cells[i, j].HorizontalAlignment = Microsoft.Office.Interop.Excel.Constants.xlCenter;
                        Microsoft.Office.Interop.Excel.Range formatRange;
                        formatRange = ExcelApp.Cells[i, j];
                        formatRange.Interior.Color = System.Drawing.
                                                     ColorTranslator.ToOle(System.Drawing.Color.CornflowerBlue);
                    }

                    else
                    {
                        ExcelApp.Cells[i, j] = dtMainSQLData.Rows[i - 2][j - 1].ToString();
                    }
                    ExcelApp.Cells[i, j].HorizontalAlignment = Microsoft.Office.Interop.Excel.Constants.xlCenter;
                }
            }
            //Save the file
            workbook.SaveToFile("Sample.xls", ExcelVersion.Version97to2003);

            //Launch the file
            System.Diagnostics.Process.Start("Sample.xls");
            ExcelApp.ActiveWorkbook.SaveCopyAs("C:\\Users\\Oanh\\Desktop\\BaoCaoSK.xls");
            ExcelApp.ActiveWorkbook.Saved = true;
            ExcelApp.Quit();
        }