gridview数据导出到EXCEL后，浏览器为什么自动关闭了？vs里显示程序还在运行

Question

 /// <summary>
        /// 导出Excel，导出所有列
        /// </summary>
        /// <param name="Response"></param>
        /// <param name="strFileName"></param>
        /// <param name="strTitle"></param>
        /// <param name="gv"></param>
        public static void ExportToExcel(HttpResponse Response, GridView gv, string strFileName, string strTitle)
        {
            for (int j = 1; j <= gv.Rows.Count; j++)
            {
                if (1 == j % 2)
                {
                    gv.Rows[j - 1].BackColor = System.Drawing.Color.FromName("#E7E7FF");
                    gv.Rows[j - 1].ForeColor = System.Drawing.Color.FromName("#4A3C8C");
                }
                else
                {
                    gv.Rows[j - 1].BackColor = System.Drawing.Color.FromName("#E7E7FF");
                    gv.Rows[j - 1].ForeColor = System.Drawing.Color.FromName("#4A3C8C");
                }
            }            gv.AllowPaging = false;
            gv.AllowSorting = false;            gv.BorderColor = System.Drawing.Color.FromName("#6600CC");
            gv.HeaderRow.BackColor = System.Drawing.Color.FromName("#6600CC");            gv.HeaderRow.ForeColor = System.Drawing.Color.White;            // 清楚缓冲区流中内容            Response.Clear();
            // 设为缓冲输出
            Response.Buffer = true;
            Response.Charset = "GB2312";
            string strtime = DateTime.Now.ToString("yyyyMMdd");
            //strtime = strtime.Replace("/", "").Replace("-", "");
            //strtime = strtime.Substring(0, strtime.IndexOf(" "));
            string str = string.Format("attachment;filename=\"" + System.Web.HttpUtility.UrlEncode(strFileName.Replace(" ", ""), System.Text.Encoding.UTF8)
                                        + "[{0}].xls", strtime);
            Response.AppendHeader("Content-Disposition", str);
            // 导出Excel格式，其中filename为Excel文件的名字，可根据要求定义
            // 如果设置为 GetEncoding("GB2312");导出的文件将会出现乱码！！！
            // 设置输出流为默认。注意：设置为简体中文utf8有时还好出错
            Response.Write("<meta http-equiv=Content-Type content=\"text/html; charset=GB2312\">");
            Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");            // 设置输出文件类型为excel文件。 
            Response.ContentType = "application/ms-excel";
            System.IO.StringWriter oStringWriter = new System.IO.StringWriter();
            System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);
            gv.Caption = strTitle;
            gv.AllowPaging = false;
            gv.HeaderStyle.Font.Bold = true;
            gv.HeaderStyle.Font.Size = 10;
            gv.Font.Size = 10;
            gv.RenderControl(oHtmlTextWriter);
            Response.Output.Write(oStringWriter.ToString());            // 刷新设计器加载程序的挂起更改
            Response.Flush();
            Response.End();
        }

Answer 1

页面点击导出，弹出对话框提示，直接打开或者下载；点击直接打开或下载，正常打开或下载EXCEL文件了，但运行的浏览器没了，VS里程序还在运行。。导出无法操作，只能重新启程程序了。。

Answer 2

hearder:attachment;filename
这是文件下载header,关闭正常。

Answer 3

把这些去掉试下。
 string str = string.Format("attachment;filename=\"" + System.Web.HttpUtility.UrlEncode(strFileName.Replace(" ", ""), System.Text.Encoding.UTF8)                                        + "[{0}].xls", strtime);            Response.AppendHeader("Content-Disposition", str);