GridView 导出Excel

前台：

 <td  style=" 150px;">
                             <asp:Button ID="btnExcel" runat="server" Text="导出Excel/Export Excel" OnClick="btnExcel_Click" Width="100%" />
                        </td>

后台：

        protected void btnExcel_Click(object sender, EventArgs e)
        {
            DateTime dt = System.DateTime.Now;
            string str = dt.ToString("yyyyMMddhhmmss");
            str = str + ".xls";

            gvDepartmentInfo.AllowPaging = false;

            gvDepartmentInfo.DataSource = GetData();
            gvDepartmentInfo.DataBind();
            GridViewToExcel(gvDepartmentInfo, "application/ms-excel", str);

            // Export(gvRecord, "application/ms-excel", str);
        }

        /// <summary>
        /// 将网格数据导出到Excel
        /// </summary>
        /// <param name="ctrl">网格名称(如GridView1)</param>
        /// <param name="FileType">要导出的文件类型(Excel:application/ms-excel)</param>
        /// <param name="FileName">要保存的文件名</param>
        public static void GridViewToExcel(Control ctrl, string FileType, string FileName)
        {
            HttpContext.Current.Response.Charset = "GB2312";
            HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");//注意编码
            HttpContext.Current.Response.AppendHeader("Content-Disposition",
                "attachment;filename=" + HttpUtility.UrlEncode(FileName, Encoding.UTF8).ToString());
            HttpContext.Current.Response.ContentType = FileType;//image/JPEG;text/HTML;image/GIF;vnd.ms-excel/msword 
            ctrl.Page.EnableViewState = false;
            StringWriter tw = new StringWriter();
            HtmlTextWriter hw = new HtmlTextWriter(tw);
            ctrl.RenderControl(hw);
            HttpContext.Current.Response.Write(tw.ToString());
            HttpContext.Current.Response.End();
        }
        public override void VerifyRenderingInServerForm(Control control)
        {

        }