//重写Page基类的OnLoad事件方法
        protected override void OnLoad(EventArgs e)
        {
            //测试
            //Session.RemoveAll();
            try
            {
                if (base.Session["user"] == null || base.Session["user"].ToString().Equals(""))
                {
                    this.ClientScript.RegisterStartupScript(GetType(), "", "<script language=javascript>top.location.href='../../Login.aspx'</script>");
                    //Response.Write("<script language=javascript>top.location.href='../../Login.aspx'</script>");
                }
                else {
                    base.OnLoad(e);
                }
            }
            catch (Exception)
            {

                throw;
            }