void ListQueueCallback(IAsyncResult ar) { try { var response = _client.EndListQueue(ar); foreach (var queueUrl in response.QueueUrls) { Console.WriteLine(queueUrl); } Console.WriteLine("\n----------------------------------------------------\n"); if (response.IsSetNextMarker()) { _nextMarker = response.NextMarker; Console.WriteLine("NextMarker: {0}", response.NextMarker); } else { _nextMarker = string.Empty; } _autoSetEvent.Set(); } catch (Exception ex) { Console.WriteLine("Async List queue failed, exception info: " + ex.Message); } }