Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        Dim facebookCookieValues As NameValueCollection = GetCookieValues("MIO_CODICE_APP")
        Dim accessToken As String = facebookCookieValues("access_token")

        Dim token As String = "[ACCESS_TOKEN]"
        Dim url As String = "https://graph.facebook.com/me?access_token=" & token
        Dim jsonUserData As String

        Using client As New WebClient()
            jsonUserData = client.DownloadString(url)
        End Using
End Sub
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Private Shared Function GetCookieValues(applicationId As String) As NameValueCollection
        Dim facebookCookieName As String = String.Concat("fbs_", applicationId)
        Dim cookie As HttpCookie = HttpContext.Current.Request.Cookies(facebookCookieName)

        If cookie Is Nothing OrElse String.IsNullOrEmpty(cookie.Value) Then
            Return Nothing
        End If

        Dim cookieValue As String = cookie.Value
        cookieValue = cookieValue.Replace("""", String.Empty)

        Return HttpUtility.ParseQueryString(cookieValue)
    End Function