iOS：outputStream不会保持打开状态

好的，所以我正在实现NSOutput和输入流。 当它们被初始化时，流打开并连接到我在PC上运行的TCPServer，但是在初始化function之外似乎关闭了一次，或者流可能没有正确存储。 我不太确定，所以非常感谢任何帮助

在我的.h文件中：

@interface AVCamViewController : UIViewController  { NSOutputStream *outputStream; NSInputStream *inputStream; } @property (retain) NSInputStream *inputStream; @property (retain) NSOutputStream *outputStream; 

在我的.m文件中：

 @synthesize inputStream, outputStream; -(void)sendaResponse { NSString *response = [NSString stringWithFormat:@"Hello from Ipad Simulator"]; NSData *data = [[NSData alloc] initWithData:[response dataUsingEncoding:NSASCIIStringEncoding]]; [outputStream write:[data bytes] maxLength:[data length]]; NSLog(@"%u", outputStream.streamStatus); } -(void)initNetworkCommunication { CFReadStreamRef readStream; CFWriteStreamRef writeStream; CFStreamCreatePairWithSocketToHost(NULL, (CFStringRef)@"10.9.100.122", 80, &readStream, &writeStream); NSInputStream *inputStream = (NSInputStream *) readStream; NSOutputStream *outputStream = (NSOutputStream *) writeStream; [inputStream setDelegate:self]; [outputStream setDelegate:self]; [inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode]; [outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode]; [inputStream open]; [outputStream open]; NSLog(@"%u and %u", inputStream.streamStatus, outputStream.streamStatus); NSString *response = [NSString stringWithFormat:@"Hello from Mikes Ipad Simulator"]; NSData *data = [[NSData alloc] initWithData:[response dataUsingEncoding:NSASCIIStringEncoding]]; [outputStream write:[data bytes] maxLength:[data length]]; NSLog(@"%u", outputStream.streamStatus); } -(void)stream:(NSStream *)aStream handleEvent:(NSStreamEvent)eventCode { switch (eventCode) { case NSStreamEventOpenCompleted: NSLog(@"Stream Opened %u", outputStream.streamStatus); break; case NSStreamEventHasBytesAvailable: if(aStream == inputStream) { uint8_t buffer [1024]; int 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); } } } } break; case NSStreamEventErrorOccurred: NSLog(@"Can not connect to the host!"); break; case NSStreamEventEndEncountered: if(aStream == inputStream) NSLog(@"Ending input stream"); if(aStream == outputStream) NSLog(@"Ending output stream"); [aStream close]; [aStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode]; [aStream release]; aStream = nil; break; default: break; } } 

在initNetworkConnection中，模拟器连接到我的TCPServer并打开连接（streamstatus = 2）。 收到消息“来自Ipad Simulator的Hello”。 但是我从按钮点击调用了“sendaResponse”方法，然后streamstatus = 0并且“outputstream”似乎没有被初始化。 我只是没有正确保留变量吗？

Answer 1

我假设你正在使用ARC。 删除此代码：

 { NSOutputStream *outputStream; NSInputStream *inputStream; } @synthesize inputStream, outputStream; 

它只会让您在属性和实例变量之间感到困惑。 拥有它的结果是您直接设置实例变量，并且您的流实例正由ARC取消分配。

相反，一旦删除了上面的代码，就可以使用self.inputStream和self.outputStream访问流。 这将允许属性正常工作，并确保遵循您配置的“保留”规范。

您的原始代码也可能不是尝试设置属性…您的配置应该是：

  NSInputStream *inputStream = (NSInputStream *) readStream; NSOutputStream *outputStream = (NSOutputStream *) writeStream; [inputStream setDelegate:self]; [outputStream setDelegate:self]; [inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode]; [outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode]; [inputStream open]; [outputStream open]; self.inputStream = inputStream; self.outputStream = outputStream; 

然后将属性更改为：

 @property (strong) NSInputStream *inputStream; @property (strong) NSOutputStream *outputStream;