点击button 弹出对话框然后 跳转页面 下载excel

Jumppage.aspx页面public partial class Jumppage : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        
    }    protected void Button1_Click(object sender, EventArgs e)
    {
        Response.Write("<script language=javascript> alert('操作成功!');location='TipBox.aspx';</script>");
    }
}
TipBox页面public partial class TipBox : System.Web.UI.Page
{
    public DataTable dtTable = new DataTable();
    public void Page_Load(object sender, EventArgs e)
    {        dtTable.Columns.Add("iuserid", typeof(string));
        dtTable.Columns.Add("username", typeof(string));
        DataRow dr;
        dr = dtTable.NewRow();
        dr["iuserid"] = "1";
        dr["username"] = "Tony";
        dtTable.Rows.Add(dr);        dr = dtTable.NewRow();
        dr["iuserid"] = "2";
        dr["username"] = "Danny";
        dtTable.Rows.Add(dr);        if (!IsPostBack)
        {
            ExportToExcel(dtTable);
        }
     }
      public void ExportToExcel(DataTable dtTable)
    {
        if (dtTable == null)
        {
            return;
        }
        HttpResponse resp;
        resp = Page.Response;
        resp.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");
        Response.ClearContent();
        Random r = new Random();
        string excelname = "" + DateTime.Now.ToString("yyyy-MM-dd") + "" + r.Next(1000, 9999) + ".xls";
        resp.AppendHeader("Content-Disposition", "attachment;filename=" + excelname);
        string colHeaders = "", ls_item = "";        DataRow[] myRow = dtTable.Select();
        int i = 0;
        int cl = dtTable.Columns.Count;        for (i = 0; i < cl; i++)
        {
            if (i == (cl - 1))
            {
                colHeaders += dtTable.Columns[i].Caption.ToString() + "\n";
            }
            else
            {
                colHeaders += dtTable.Columns[i].Caption.ToString() + "\t";
            }        }
        //resp.Write(colHeaders);
        resp.Write(colHeaders);        foreach (DataRow row in myRow)
        {            for (i = 0; i < cl; i++)
            {
                if (i == (cl - 1))
                {
                    ls_item += row[i].ToString() + "\n";
                }
                else
                {
                    ls_item += row[i].ToString() + "\t";
                }            }
            //resp.Write(ls_item);
            resp.Write(ls_item);
            ls_item = "";        }
        resp.End();
    }
}效果是点击Button 弹出对话框"操作成功！",再点击框上的确定后,页面上出现
，在右键点击这个图片上的框, 点击download file ,页面又会再一次弹出操作成功，点击确定之后,弹出打开 保存 取消框.
怎么可以不让IE弹出那个图片呀?