Objective-C TCP通讯实例

{% codeblock Communicator.h lang:objc%} #import <Foundation/Foundation.h>

@interface Communicator : NSObject{
@public

NSString *host;
int port;

}

• (void)setup;
• (void)open;
• (void)close;
• (void)stream:(NSStream *)stream handleEvent:(NSStreamEvent)event;
• (void)readIn:(NSString *)s;
• (void)writeOut:(NSString *)s;

@end {% endcodeblock %}

{% codeblock Communicator.m lang:objc%} #import “Communicator.h”

CFReadStreamRef readStream;
CFWriteStreamRef writeStream;

NSInputStream *inputStream;
NSOutputStream *outputStream;

@implementation Communicator

• (void)setup {
  NSURL *url = [NSURL URLWithString:host]; NSLog(@“Setting up connection to %@ : %i”, [url absoluteString], port);

  CFStreamCreatePairWithSocketToHost(kCFAllocatorDefault, (CFStringRef)[url host], port, &readStream, &writeStream);
  
  if(!CFWriteStreamOpen(writeStream)) {
      NSLog(@"Error, writeStream not open");
  
      return;
  }
  [self open];
  
  NSLog(@"Status of outputStream: %i", [outputStream streamStatus]);
  
  return;
  

  }

• (void)open {
  NSLog(@“Opening streams.”); inputStream = (NSInputStream *)readStream; outputStream = (NSOutputStream *)writeStream;

  [inputStream retain];
  [outputStream retain];
  
  [inputStream setDelegate:self];
  [outputStream setDelegate:self];
  
  [inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
  [outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
  
  [inputStream open];
  [outputStream open];
  

  }

• (void)close {
  NSLog(@“Closing streams.”); [inputStream close]; [outputStream close];

  [inputStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
  [outputStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
  
  [inputStream setDelegate:nil];
  [outputStream setDelegate:nil];
  
  [inputStream release];
  [outputStream release];
  
  inputStream = nil;
  outputStream = nil;
  

  }

• (void)stream:(NSStream *)stream handleEvent:(NSStreamEvent)event {
  NSLog(@“Stream triggered.”); switch(event) { case NSStreamEventHasSpaceAvailable: { if(stream == outputStream) { NSLog(@“outputStream is ready.”); } break; } case NSStreamEventHasBytesAvailable: { if(stream == inputStream) { NSLog(@“inputStream is ready.”);

              uint8_t buf[1024];
              unsigned int len = 0;
  
              len = [inputStream read:buf maxLength:1024];
  
              if(len > 0) {
                  NSMutableData* data=[[NSMutableData alloc] initWithLength:0];
  
                  [data appendBytes: (const void *)buf length:len];
  
                  NSString *s = [[NSString alloc] initWithData:data encoding:NSASCIIStringEncoding];
  
                  [self readIn:s];
  
                  [data release];
              }
          }
          break;
      }
      default: {
          NSLog(@"Stream is sending an Event: %i", event);
  
          break;
      }
  }
  

  }

• (void)readIn:(NSString *)s {
  NSLog(@“Reading in the following:”);
  NSLog(@”%@”, s);
  }

• (void)writeOut:(NSString *)s {
  uint8_t *buf = (uint8_t *)[s UTF8String]; [outputStream write:buf maxLength:strlen((char *)buf)];

  NSLog(@"Writing out the following:");
  NSLog(@"%@", s);
  

  }

@end {% endcodeblock %}

{% codeblock StreamExample.m lang:objc%} #import <Foundation/Foundation.h>

#import “Communicator.h”

int main (int argc, const char _ argv[]) {
NSAutoreleasePool _ pool = [[NSAutoreleasePool alloc] init];

Communicator *c = [[Communicator alloc] init];

c->host = @"http://127.0.0.1";
c->port = 6789;

[c setup];
[c open];

[pool drain];

return 0;

}
{% endcodeblock %}