从http://aspalliance.com/1621_Implementing_a_Session_Timeout_Page_in_ASPNET.2

namespace SessionExpirePage
{
    public partial class Secure : System.Web.UI.MasterPage
    {
        public int SessionLengthMinutes
        {
            get { return Session.Timeout; }
        }
        public string SessionExpireDestinationUrl
        {
            get { return "/SessionExpired.aspx"; }
        }
        protected override void OnPreRender(EventArgs e)
        {
            base.OnPreRender(e);
            this.PageHead.Controls.Add(new LiteralControl(
                String.Format("<Meta http-equiv='refresh' content='{0};url={1}'>",SessionLengthMinutes*60,SessionExpireDestinationUrl)));
        }
    }
}

SessionExpireDestinationUrl应链接到您清除会话和任何其他用户数据的页面。

刷新页眉到期时，会自动将其重定向到该页面。