一个.net导出excel比较简单的办法，代码如下，但必须要重写一个方法，不然在执行RenderControl(hw)这句代码时报错。

            string _fileXls = string.Format("{0}{1}", "Patty Cash", DateTime.Now.ToString(CommonDefine.DATE_FORMAT_LIST));
            HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=" + _fileXls + ".xls");
            HttpContext.Current.Response.Charset = "gb2312";
            HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312");
            HttpContext.Current.Response.ContentType = "application/ms-excel";
            this.gvList.Page.EnableViewState = false;
            System.IO.StringWriter tw = new System.IO.StringWriter();
            System.Web.UI.HtmlTextWriter hw = new System.Web.UI.HtmlTextWriter(tw);
            this.gvList.RenderControl(hw);
            HttpContext.Current.Response.Write(tw.ToString());
            HttpContext.Current.Response.End();

要重载的方法：

        public override void VerifyRenderingInServerForm(System.Web.UI.Control control)
        {
            //base.VerifyRenderingInServerForm(control);
        }