当我使用以下代码时,出现错误消息:[NSURLConnectionsendAsynchronousRequest:requestqueue:myQueuecompletionHandler:^(NSURLResponse*response,NSData*data,NSError*error){NSHTTPURLResponse*httpResponse=(NSHTTPURLResponse*)response;NSLog(@"responsestatuscode:%ld,errorstatus:%@",(long)[httpResponsestatusCode],error.descr