使用OC二进制流进行发送消息

//ios这里实现socket的链接，使C语言

//1.与服务器通过三次握手实现链接

NSString *host = @"127.0.0.1";

int port = 54321;

CFReadStreamRef readStream;        CFWriteStreamRef writeStream;

//3.分配输入输出流的内存空间CFStreamCreatePairWithSocketToHost(NULL, (__bridge  CFStringRef)host,port,&readStream, &writeStream);

//4.把C语言的输入输出流转成OC对象

_inputStream = (__bridge NSInputStream *)(readStream);

_outputStream = (__bridge NSOutputStream *)(writeStream);

//5.设置代理，监听数据接收的状态

_outputStream.delegate = self;

_inputStream.delegate = self;

[_outputStream scheduleInRunLoop:[NSRunLoop mainRunLoop] forMode:NSDefaultRunLoopMode];

[_inputStream scheduleInRunLoop:[NSRunLoop mainRunLoop] forMode:NSDefaultRunLoopMode];

//6打开输入输出流

[_inputStream open];

[_outputStream open];

#pragma mark--- NSStreamDelegate

-(void)stream:(NSStream *)aStream handleEvent:(NSStreamEvent)eventCode{

switch (eventCode) {

case NSStreamEventOpenCompleted:

NSLog(@"成功建立链接，形成输入输出流的传输通道");

break;

case NSStreamEventHasBytesAvailable:

NSLog(@"有数据可读");

[self readData];

break;case NSStreamEventHasSpaceAvailable:NSLog(@"可以发送数据");break;case NSStreamEventEndEncountered:NSLog(@"正常的断开链接");//断开连接时，把输入输出流关闭，而且还要从主运行循环中移除[_inputStream close];[_outputStream close];[_inputStream removeFromRunLoop:[NSRunLoop mainRunLoop] forMode:NSDefaultRunLoopMode];[_outputStream removeFromRunLoop:[NSRunLoop mainRunLoop] forMode:NSDefaultRunLoopMode];break;default:break;}