前台:{
                     id: 'print', iconCls: 'icon-print', text: '导出', handler: function () {
                         var filterRules = $('#dg').datagrid('options').filterRules;
                         var filters = "";
                         if (filterRules.length > 0) {
                             filters = "[";
                             for (var i = 0; i < filterRules.length; i++) {
                                 if (i > 0) {
                                     filters += ",";
                                 }
                                 filters += "{\"field\":\"" + filterRules[i].field + "\",\"op\":\"" + filterRules[i].op + "\",\"value\":\"" + filterRules[i].value + "\"}";
                             }
                             filters += "]";
                         }
                         window.open("/Test/Test/TestDataQuery?export=y&filterRules=" + filters);
                     }
                 }

后台:　　　　public ActionResult TestDataQuery()
        {　　　　　　　　　　　　　　private Entitie db = new Entitie();
           //查询语句
            string sql = "select t.ID,t.TEST1,t.TEST2,t.TEST3,t.TEST4,t.TEST5 from test t";
            //----导出参数
            string excelname = "测试表";
            string[] excelcol = { "测试1", "测试2", "测试3", "测试4", "测试5" };　　　　　　　　
　　　　　　　DataTable dt = DbHelperOrcl.GetDTQuery(db.Database.Connection.ConnectionString, sql);/　　　　　　　if (Request["export"] == "y")            {                GridExport(dt, excelname, excelcol);            }
            string jsonData = GetJeJsonData(db.Database.Connection.ConnectionString, sql, Request, excelname, excelcol);
            return Content(jsonData);
          
        }

导出:public static void GridExport(DataTable dt, string excelname, string[] excelcol)
        {
            HSSFWorkbook workbook = new HSSFWorkbook();
            ISheet sheet = workbook.CreateSheet("Sheet1");
            ICell cells;
            //--------------------------------------------------------------------
            ICellStyle styles = GetStyles(workbook);//普通样式
            ICellStyle styles_zd = GetzdStyles(workbook);//表头字段样式
            //----------------------标题-----------------------------------------------
           //CellRangeAddress四个参数为：起始行，结束行，起始列，结束列
            sheet.AddMergedRegion(new CellRangeAddress(0, 0, 0, dt.Columns.Count-1));
            //----------------------表头-----------------------------------------------
            cells = sheet.CreateRow(0).CreateCell(0);
            cells.SetCellValue(excelname);
            cells.CellStyle = styles_zd;
            int col_head = 0;
            for (int j = 0; j < dt.Columns.Count; j++)
            {
                string name = dt.Columns[j].ColumnName;
                if (col_head == 0)
                {
                    cells = sheet.CreateRow(1).CreateCell(col_head);
                }
                else
                {
                    cells = sheet.GetRow(1).CreateCell(col_head);
                }
                cells.SetCellValue(name);
                cells.CellStyle = styles_zd;
                col_head++;
                if (name == "ID" || name == "id")
                {
                    sheet.SetColumnHidden(0, true);
                }
            }
            //----------------------数据-----------------------------------------------
            int rowno = 1;
            foreach (DataRow dr in dt.Rows)
            {
                int cellno = 0;
                for (int i = 0; i < dt.Columns.Count; i++)
                {
                    object value = dr[i];
                    //如果非空，则赋给对象的属性  
                    if (cellno == 0)
                    {
                        cells = sheet.CreateRow(rowno).CreateCell(cellno);
                    }
                    else
                    {
                        cells = sheet.GetRow(rowno).CreateCell(cellno);
                    }
                    if (value != DBNull.Value)
                    {
                        cells.SetCellValue(value.ToString());
                    }
                    cells.CellStyle = styles;
                    cellno += 1;
                }
                rowno += 1;
            }
            HttpResponse response= System.Web.HttpContext.Current.Response;
            string filename = excelname!=null? excelname+".xls" : "数据.xls";
            response.ContentType = "application/vnd.ms-excel";
            response.AddHeader("Content-Disposition", string.Format("attachment;filename={0}", filename));
            response.Clear();
            response.BinaryWrite(WriteToStream(workbook).GetBuffer());
            response.End();
        }不喜勿喷！！！纯属个人经验