C#导出GridView数据到Excel的方法

        /// <summary>
        /// 将GridView的数据导出为Excel表
        /// </summary>
        /// <param name="ctl">控件ID</param>
        public void ExportToExcel(System.Web.UI.Control ctl)
        {
            string filename = "RP05.xls";

            HttpContext.Current.Response.Clear();
            HttpContext.Current.Response.Buffer = true;
            HttpContext.Current.Response.Charset = "UTF-8";
            HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("UTF-8");
            HttpContext.Current.Response.ContentType = "application/ms-excel";
            HttpContext.Current.Response.AppendHeader("content-disposition", "attachment;filename=\"" +
                System.Web.HttpUtility.UrlEncode(filename, System.Text.Encoding.UTF8) + "\"");
            HttpContext.Current.Response.Write("<meta http-equiv=Content-Type content=\"text/html; charset=UTF-8\">");
            ctl.Page.EnableViewState = false;
            System.IO.StringWriter tw = new System.IO.StringWriter();
            HtmlTextWriter hw = new HtmlTextWriter(tw);
            ctl.RenderControl(hw);
            HttpContext.Current.Response.Write(tw.ToString());
            HttpContext.Current.Response.End();

        }

        /// <summary>
        /// 该方法必须存在，要不不能导出Excel数据
        /// </summary>
        /// <param name="control"></param>
        public override void VerifyRenderingInServerForm(Control control)