如何最好地检测ASP.NET过期会话?

我需要在我的visuial基本web应用程序中检测会话何时过期。这就是我要用的……

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

    If CurrentSession.IsNew AndAlso (Not Page.Request.Headers("Cookie") Is Nothing) AndAlso (Page.Request.Headers("Cookie").IndexOf("ASP.NET_SessionId") >= 0) Then
        Response.Redirect("TimeOut.aspx")
    End If

    ...do something...

End Sub

注: CurrentSession.IsNew 收益率 HttpContext.Current.Session.IsNewSession

这似乎对 Internet Explorer 但似乎失败了 火狐 .