基于TCP的客户端通信在iOS11中不起作用？

我有一个使用Socket编程与设备通信的IoT应用程序.一切顺利,直到iOS 11发布.它在iOS 11及更高版本中不通信,但它适用于早期版本(最多10个).这是代码.

建立套接字连接

(void)setUpSocketConnection {
    @try {
        CFStreamCreatePairWithSocketToHost(kCFAllocatorDefault, (__bridge CFStringRef) VeranoHost,VeranoPort , &readStream, &writeStream);
        [self open];
    }
    @catch (NSException *exception) {
        NSLog(@"Open Exception:%@", exception.reason);
    }   
}

打开流

(void)open {
    //NSLog(@"Opening streams.");
    _outputStream = (__bridge  NSOutputStream *)writeStream;
    _inputStream = (__bridge  NSInputStream *)readStream;
    [_outputStream setDelegate:self];
    [_inputStream setDelegate:self];

    dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH,0);
    dispatch_async(queue, ^ {
            [_outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
            [_inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
            [[NSRunLoop currentRunLoop] run];
    });

    [_outputStream open];
    [_inputStream open];

    //[self disableNaglesAlgorithmForStream:_inputStream];
   // NSLog(@"Connected");
//    self.timeOutTimer = [NSTimer scheduledTimerWithTimeInterval:10.0
//                                                         target:self
//                                                       selector:@selector(timerTimeOutAction:)
//                                                       userInfo:nil
//                                                        repeats:NO];
}

写入输出流

(void)writeData:(NSString *)message forSocketType:(SOCKETTTYPE)socketType {
    self.socketType = socketType;
    NSData *data = [[NSData alloc] initWithData:[message dataUsingEncoding:NSASCIIStringEncoding]];
    [_outputStream write:[data bytes] maxLength:[data length]];
    [_outputStream close];

}

事件处理程序

(void)stream:(NSStream *)theStream handleEvent:(NSStreamEvent)streamEvent {
   // NSLog(@"stream event %lu", (unsigned long)streamEvent);
    switch (streamEvent) {
        case NSStreamEventOpenCompleted:{

           // NSLog(@"NSStreamEventOpenCompleted :::: Stream opened and connected");
        }
            break;
        case NSStreamEventHasBytesAvailable:
            // NSLog(@"NSStreamEventHasBytesAvailable :::: Stream opened and connected");
            if (theStream == _inputStream) {
                uint8_t buffer[1024];
                NSInteger len;

                while ([_inputStream hasBytesAvailable])
                {
                    len = [_inputStream read:buffer maxLength:sizeof(buffer)];
                    if (len > 0)
                    {
                        NSString *output = [[NSString alloc] initWithBytes:buffer length:len encoding:NSASCIIStringEncoding];

                        if (nil != output)
                        {
                            NSLog(@"server said: %@", output);
                            [self messageReceived:output];
                        }
                    }
                }
            }
            break;
        case NSStreamEventHasSpaceAvailable:
           // NSLog(@"NSStreamEventHasSpaceAvailable :::: Stream has space available now");
            break;

        case NSStreamEventErrorOccurred:{
           NSError *theError = [theStream streamError];
            NSLog(@"Error Description:%@",theError.localizedDescription);
            [self close];
            if(self.delegate &&[self.delegate respondsToSelector:@selector(socketHandlerItem:failureWithError:forSocketType:)]){
                [self.delegate socketHandlerItem:self failureWithError:[theStream streamError] forSocketType:self.socketType];
            }
             //NSLog(@"NSStreamEventErrorOccurred :::: %@",[theStream streamError].localizedDescription);
        }
            break;

        case NSStreamEventEndEncountered:
            [theStream close];
            [theStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
            if(self.delegate &&[self.delegate respondsToSelector:@selector(socketHandlerItem:eventStopedWithstatus:forSocketType:)]){
                [self.delegate socketHandlerItem:self eventStopedWithstatus:YES forSocketType:self.socketType];
            }
           // NSLog(@"NSStreamEventEndEncountered :::: close stream Disconnected");
            break;
        default:
           // NSLog(@"Unknown event");
            break;
    }
}

因此,当连接到套接字时,它进入 NSStreamEventErrorOccurred事件处理程序和日志 -The operation couldn’t be completed. No route to host

任何帮助将不胜感激.

2017年12月19日更新

有一个Reachability包装器,允许发现主机地址,我可以确认它返回NetworkStatusReachableViaWiFi

套接字通信工作正常,我尝试通过创建示例服务器套接字,能够发送和接收数据.

2017年12月20日更新(1)

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用户手册在这里

2017年12月20日更新(2)

Eurekaa,但解决方案无法实时应用.在iOS 11中设置与IoT模块的主机地址对应的最近静态IP地址范围时,通信正常.但它不适用于动态分配的IP地址.