(OAuthException - #2500) Einen aktiven access token muss verwendet werden, zur Abfrage von Informationen über den aktuellen Benutzer

        string accessToken = GetAccessToken();
        string accessKey = accessToken.Split('=')[1];

        var client = new FacebookClient(accessKey);
        dynamic me = client.Get("me");

hier ist die Methode auf get access token und es tut Rückkehr einen gültigen access-token

private static string GetAccessToken()
    {
        //Create a request using a URL that can receive a post. 
        WebRequest request = WebRequest.Create("https://graph.facebook.com/oauth/access_token?grant_type=client_credentials&client_id=201193246663533&client_secret=secretkeyhere");
        //Set the Method property of the request to POST.
        request.Method = "POST";
        //Create POST data and convert it to a byte array.
        string postData = "This is a test that posts this string to a Web server.";
        byte[] byteArray = Encoding.UTF8.GetBytes(postData);
        //Set the ContentType property of the WebRequest.
        request.ContentType = "application/x-www-form-urlencoded";
        //Set the ContentLength property of the WebRequest.
        request.ContentLength = byteArray.Length;
        //Get the request stream.
        Stream dataStream = request.GetRequestStream();
        //Write the data to the request stream.
        dataStream.Write(byteArray, 0, byteArray.Length);
        //Close the Stream object.
        dataStream.Close();
        //Get the response.
        WebResponse response = request.GetResponse();
        //Display the status.
        Console.WriteLine(((HttpWebResponse)response).StatusDescription);
        //Get the stream containing content returned by the server.
        dataStream = response.GetResponseStream();
        //Open the stream using a StreamReader for easy access.
        StreamReader reader = new StreamReader(dataStream);
        //Read the content.
        string responseFromServer = reader.ReadToEnd();
        //Display the content.
        Console.WriteLine(responseFromServer);
        //Clean up the streams.
        reader.Close();
        dataStream.Close();
        response.Close();

        return responseFromServer;
    }

Allerdings, wenn ich Debuggen über

dynamic me = client.Get("me");

wirft diese exception:

(OAuthException - #2500) Einen aktiven access token muss verwendet werden, zur Abfrage von Informationen über den aktuellen Benutzer.

Wie kann ich dieses Problem beheben?

InformationsquelleAutor DarthVader | 2012-04-10