Vb.net FormsAuthenticationCookie缓存

我遇到一个问题，我的authcookie没有在浏览器关闭时被删除，或者当其他用户登录时

我的cookie在此声明：

If ModelState.IsValid Then

                'check username and password
                If model.pwd = db.users.First(Function(t) t.NT_id = model.NT_id).pwd Then

                    'create an authentication cookie
                    FormsAuthentication.SetAuthCookie(model.NT_id, False) 'set to false to destroy cookie on browser close

                    'redirect action if login is successful
                    Return RedirectToAction("Construction", "Home")
                Else
                    ModelState.AddModelError("", "Invalid Username or Password")
                End If
            End If
            Return View(model)

我知道这不会删除cookie，因为我有一个变量来显示cookie用户名

Public Shared uNT_id = If(HttpContext.Current.User.Identity.IsAuthenticated, HttpContext.Current.User.Identity.Name, System.Environment.UserName)

---

通过使用get和set将所有变量转换为属性以停止缓存，可以解决这个问题

Public Class userinfo
        Public Shared Property uNT_id As String
            Get
                If HttpContext.Current.User.Identity.IsAuthenticated Then
                    Return HttpContext.Current.User.Identity.Name
                Else
                    Return System.Environment.UserName
                End If
            End Get
            Set(value As String)
                If HttpContext.Current.User.Identity.IsAuthenticated Then
                    value = HttpContext.Current.User.Identity.Name
                Else
                    value = System.Environment.UserName
                End If
            End Set
        End Property

        Public Shared Property uid As String
            Get
                Return db_apps.app_users.First(Function(t) t.NT_id = uNT_id).app_user_id
            End Get
            Set(value As String)
                value = db_apps.app_users.First(Function(t) t.NT_id = uNT_id).app_user_id
            End Set
        End Property

        Public Shared Property ussn As Integer
            Get
                Return db_apps.app_users.First(Function(t) t.NT_id = uNT_id).ssn
            End Get
            Set(value As Integer)
                value = db_apps.app_users.First(Function(t) t.NT_id = uNT_id).ssn
            End Set
        End Property

        Public Shared Property upwd As String
            Get
                Return db_apps.app_users.First(Function(t) t.NT_id = uNT_id).pwd
            End Get
            Set(value As String)
                value = db_apps.app_users.First(Function(t) t.NT_id = uNT_id).pwd
            End Set
        End Property

        Public Shared Property uname_first As String
            Get
                Return db_apps.app_users.First(Function(t) t.NT_id = uNT_id).name_first
            End Get
            Set(value As String)
                value = db_apps.app_users.First(Function(t) t.NT_id = uNT_id).name_first
            End Set
        End Property
    End Class

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我觉得它实际上是在兑现信息，即使我已经将cookie持久性设置为false。。。