//调用
 public ActionResult GenerateExcel() {
            DataTable headerTable = new DataTable();
            headerTable.Columns.Add("Status_Id", Type.GetType("System.String"));
            headerTable.Columns.Add("Status_Name", Type.GetType("System.String"));
            headerTable.Columns.Add("Is_Now", Type.GetType("System.String"));
            headerTable.Columns.Add("Curr_User_Id", Type.GetType("System.String"));
            headerTable.Columns.Add("Flow_Id", Type.GetType("System.String"));
           
            DataRow headerRow = headerTable.NewRow();
            headerRow["Status_Id"] = "Status_Id";
            headerRow["Status_Name"] = "Status_Name";
            headerRow["Is_Now"] = "Is_Now";
            headerRow["Curr_User_Id"] = "Curr_User_Id";
            headerRow["Flow_Id"] = "Flow_Id";
            headerTable.Rows.Add(headerRow);

            DataTable contentTable = getDataByProc();

            generateExcelOP(headerTable, contentTable);
            ViewData["result"] = "Create successfully";
            return View("ExcelUpload");
        }

        //生成Excel

        public void generateExcelOP(DataTable headerTable,DataTable dt) {

            HSSFWorkbook workbook = new HSSFWorkbook();
            HSSFSheet sheet = workbook.CreateSheet() as HSSFSheet;

            //excel header info
            HSSFRow headerRow = sheet.CreateRow(0) as HSSFRow;
            for(int i = 0 ;i < headerTable.Columns.Count;i++){
                HSSFCell headerCell = headerRow.CreateCell(i) as HSSFCell;
                headerCell.SetCellValue(headerTable.Rows[0][i].ToString());
                headerRow.Cells.Add(headerCell);
            }

            //excel content info
            for(int m =0 ;m < dt.Rows.Count;m++){
                HSSFRow row = sheet.CreateRow((m+1)) as HSSFRow;
                for (int n = 0; n < dt.Columns.Count;n++ )
                {
                    HSSFCell cell = row.CreateCell(n) as HSSFCell;
                    cell.SetCellValue(dt.Rows[m][n].ToString());
                    row.Cells.Add(cell);
                }
            }

            FileStream fs = new FileStream(@"D:\data\output.xls", FileMode.Create);
            workbook.Write(fs);
            fs.Flush();
            fs.Close();
            workbook.Clear();
        }

       //获取数据

        public DataTable getDataByProc() {
            DataTable dt = new DataTable();
            string callName = "GetAuthHistory";
            string devConn = System.Configuration.ConfigurationManager.ConnectionStrings["devConn"].ToString();
            using(SqlConnection conn = new SqlConnection(devConn)){
                SqlCommand command = new SqlCommand(callName, conn);
                command.CommandType = CommandType.StoredProcedure;
                SqlParameter[] sps = {
                                     new SqlParameter("@currPage",SqlDbType.Int),
                                      new SqlParameter("@pageSize",SqlDbType.Int)
                                     };
                sps[0].Value = 1;
                sps[1].Value = 20;
               foreach(SqlParameter sp in sps){
                   command.Parameters.Add(sp);
               }
               SqlDataAdapter sda = new SqlDataAdapter();
               sda.SelectCommand = command;
               sda.Fill(dt);
            }

            return dt;
        }