c#导出Excel

 protected void btnExport_Click(object sender, EventArgs e)
        {
            DataTable dt = (DataTable)ViewState["TableAll"];
            DataTable dtSerch = (DataTable)ViewState["SerchTable"];
            if (dtSerch != null)
            {
                Repeater1.DataSource = dtSerch;
                Repeater1.DataBind();
            }
            else
            {
                Repeater1.DataSource = dt;
                Repeater1.DataBind();
            }
            string str = DateTime.Now.ToString("yyyyMMddHHmmss");
            string str2 = "航线贴点分析报表(" + str + ")";
            Response.Clear();
            Response.Buffer = true;
            Response.Charset = "utf-8";
            Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312");
            this.Response.AppendHeader("Content-Disposition", "attachment;filename=" + System.Web.HttpUtility.UrlEncode(str2, System.Text.Encoding.UTF8) + ".xls");
            Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312");     //设置输出流为简体中文
            this.Response.ContentType = "application/ms-excel";
            this.EnableViewState = false;
            StringWriter strWriter = new StringWriter();
            HtmlTextWriter htmlWriter = new HtmlTextWriter(strWriter);
            htmlWriter.Write("<div align=center height=25 valign=middle><font size='6'>航线贴点分析报表</font></div><br>");

            this.Div1.RenderControl(htmlWriter);

            Response.Write(strWriter.ToString());
            Response.End();
        }