ASP.NET会话超时重定向不起作用

我遇到以下问题

我在Global.asax中添加了此代码

Sub Session_Start(ByVal sender As Object, ByVal e As EventArgs)
    ' Code that runs when a new session is started

    Session("Startdatetime") = DateTime.Now

End Sub

并在会话结束时发送电子邮件通知，告诉我会话结束正在启动 sessionValue是SessionStartdatetime

Sub Session_End(ByVal sender As Object, ByVal e As EventArgs)
       emailCenter.sendNotification(sessionvalue, "Session_End", "myemail@gmail.com")
 End Sub

然后在Default.aspx/page加载中，如果会话过期，则调用此方法返回true

If IsSessionExpired() Then
        Response.Redirect("sessionTimeout.html")
 End If

Public Function IsSessionExpired() As Boolean
            '??? not working
        If HttpContext.Current.Session IsNot Nothing Then
            If (HttpContext.Current.Session.IsNewSession) Then

                Dim CookieHeaders As String = HttpContext.Current.Request.Headers("Cookie")

                If IsNothing(CookieHeaders) And (CookieHeaders.IndexOf("ASP.NET_SessionId") >= 0) Then
                    ' IsNewSession is true and session cookie exists,
                    ' so, ASP.NET session is expired

                    Return True
                End If
            End If
        End If

        ' Session is not expired and function will return False, 
        ' it could be new session, or existing active session
        Return False
    End Function

我已经在web.config中设置了它，将超时设置为1分钟

<sessionState mode="InProc" cookieless="UseCookies" timeout="1" />

会话结束正在触发，但IsSessionExpired永远不会返回true

我没有使用母版页进行此测试

---

发生了什么事？

如果没有CookieHeaders，那么它应该是如果没有CookieHeaders？是的，我找到了。应该是：如果没有，那么是：如果没有CookieHeaders和CookieHeaders.IndexOfASP.NET\u SessionId>=0