//导出excel表格
        public void OutExcel(DataSet ds,string fileName) 
        {
            Response.Clear();
            Response.Buffer = true;
            Response.AddHeader("content-disposition", "attachment; filename=" + fileName + DateTime.Now.ToString("yyyyMMdd") + ".xls");
            Response.ContentType = "application/vnd.ms-excel";
            //Response.ContentType = "application/vnd.ms-word";
            Response.ContentEncoding = System.Text.Encoding.UTF8;
            Response.Charset = "";
            this.EnableViewState = false;
            StringWriter oStringWriter = new StringWriter();
            HtmlTextWriter oHtmlTextWriter = new HtmlTextWriter(oStringWriter);


            DataGrid dg = new DataGrid();
            dg.DataSource = ds; //数据源DataSet/DataTable/List<>/IList
            dg.DataBind();

            dg.RenderControl(oHtmlTextWriter);
            Response.Write(oStringWriter.ToString());
            Response.End();
        }