asp.net导出excel表

 public void OutPutExcel(string filename)
        {
            //定义文档类型、字符编码 
            Response.Clear();
            Response.Buffer = true;
            Response.Charset = "GB2312";
            //下面这行很重要， attachment 参数表示作为附件下载，您可以改成 online在线打开 
            //filename=FileFlow.xls 指定输出文件的名称，注意其扩展名和指定文件类型相符，可以为：.doc 　　 .xls 　　 .txt 　　.htm 
            Response.AppendHeader("Content-Disposition", "attachment;filename=" + filename);
            Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");
            //Response.ContentType指定文件类型 可以为application/ms-excel、application/ms-word、application/ms-txt、application/ms-html 或其他浏览器可直接支持文档 
            Response.ContentType = "application/ms-excel";
            this.EnableViewState = false;
            //　定义一个输入流 
            System.IO.StringWriter oStringWriter = new System.IO.StringWriter();
            System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);

            this.GridView1.RenderControl(oHtmlTextWriter);
            //this.RenderControl(oHtmlTextWriter); 
            //this 表示输出本页，你也可以绑定datagrid,或其他支持obj.RenderControl()属性的控件 
            Response.Write(oStringWriter.ToString());
            Response.End();
        }
        public override void VerifyRenderingInServerForm(Control control)
        {
            // Confirms that an HtmlForm control is rendered for
        }