IOS的网络通信的方法 (转）

ios设备的网络通信的方法，有如下两个大类：

1、使用socket的方式进行通信。

2、使用asynsocket类库进行通信。

两种方法当中，我觉得asynsocket更好，因为是别人已经封装好的类库，比较稳定。但是对于直接使用socket的通信方法我倒是觉得很灵活。因为控制都是自己在做的事情。

先列举集中不同的使用方法：

1、直接使用socket的方式。

以 TCP为利，对于TCP来说，是要区分服务端和客户端的。服务端：通常的方法是服务端启动后监听，是否有客户端连接，如果有连接，则建立与客户端的通信。客户端的方法通常是连接服务端，当连接成功之后，就希望发送数据了。

客户端：

CFSocketContext sockContext ;

CFSocketRef  cfsock ;

 

sockContext.info = self;

sockContext.copyDescription = 0;

 

cfsock = CFSocketCreate(kCFAllocatorDefault,

PF_INET,

SOCK_STREAM,

IPPROTO_TCP,

kCFSocketConnectCallBack,

MyCallBack,

&sockContext

);

 

 

 

// 这个地方是个关键的地方，就是建立一个ip地址，然后使的客户端可以向服务端发起连接。

NSString  *strAddress = @"192.168.1.1";

 

 

 

if (cfsock != nil) {

 

struct sockaddr_in addr4; 

 

memset(&addr4,0,sizeof(addr4));

 

addr4.sin_len = sizeof(addr4);

 

addr4.sin_family = AF_INET;

 

addr4.sin_port = htons(1230);

 

addr4.sin_addr.s_addr = inet_addr( [strAddress UTF8String] );

 

CFDataRef address = CFDataCreate(kCFAllocatorDefault, (UInt8*)&addr4, sizeof(addr4));

 

CFSocketConnectToAddress(cfsock, address, -1);

}

 

 

// 发起连接之后，需要将runloop的过程，也就是消息的过程加入到当前线程当中。这样当有事件发生时，会调用对应的方法。

 

CFRunLoopRef crun = CFRunLoopGetCurrent();// CFRunLoopGetMain();

CFRunLoopSourceRef source = CFSocketCreateRunLoopSource(kCFAllocatorDefault, cfsock, 0);

 

CFRunLoopAddSource(crun, source, kCFRunLoopCommonModes);

 

CFRelease(source);

 

回调函数：当连接成功之后的处理如下：

 

 

static void MyCallBack (

CFSocketRef          s,

CFSocketCallBackType callbackType,

CFDataRef    address,

const void   *data,

void         *info

)

{

 

if (data!=NULL) {

NSLog(@"传输失败!");

}

 

SocketTestAppDelegate *client = (SocketTestAppDelegate*)info;

 

[client performSelectoInBackground:@selector(readstream) withObject:nil];

 

 

}

 

-(void) readstream

{

char buffer[1024];

 

NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

 

while (recv(CFSocketGetNative(cfsock),buffer,sizeof(buffer),0)) {

 

}

 

[pool release];

}

//  如果希望直接向服务器写内容的话，采用如下的方法。

-(void) sendstream

{

NSString * stringtosend = @"hello everyone";

 

const char *data = [stringtosend UTF8String];

 

send(CFSocketGetNative(cfsock),data,strlen(data)+1,0);

}

 

服务器端的程序：

 

 

CFSocketRef socketserver;

int setupSocket()

{

socketserver =CFSocketCreate(kCFAllocatorDefault,PF_INET,SOCK_STREAM,IPPROTO_TCP,kCFSocketAcceptCallBack,myaccept,NULL);

 

int optval =1;

 

setsockopt(CFSocketGetNative(socketserver), SOL_SOCKET, SO_REUSEADDR, (void*)&optval,sizeof(optval));

 

struct sockaddr_in addr4;

 

memset(&addr4,0,sizeof(addr4));

 

addr4.sin_len = sizeof(addr4);

 

addr4.sin_family = AF_INET;

 

addr4.sin_port = htons(10);

addr4.sin_addr.s_addr=htonl(INADDR_ANY);

 

CFDataRef  address = CFDataCreate(kCFAllocatorDefault, (UInt8*)&addr4, sizeof(addr4));

 

CFSocketSetAddress(socketserver, address);

 

CFRunLoopRef cfRunloop = CFRunLoopGetCurrent();

 

CFRunLoopSourceRef source = CFSocketCreateRunLoopSource(kCFAllocatorDefault, socketserver, 0);

 

CFRunLoopAddSource(cfRunloop, source, kCFRunLoopCommonModes);

 

CFRelease(source);

 

}

 

//服务端的socket建立之后，就需要接受client的连接，因此建立连接的回调函数。

 

 

static void myaccept (

CFSocketRef          s,

CFSocketCallBackType callbackType,

CFDataRef    address,

const void   *data,

void         *info

)

{

 

if (callbackType == kCFSocketAcceptCallBack) {

 

 

// 如果对端连接成功的话，是可以获取对端的名称和socket的。

 

CFSocketNativeHandle nativesockethandle = *(CFSocketNativeHandle*)data;

 

uint8_t name[100];

socklen_t namelen = 100;

 

getpeername(nativesockethandle, (struct sockaddr *)name, &namelen);

 

//除此以外，更重要的是获取输入流 和 输出流，

 

CFReadStreamRef iStream;

CFWriteStreamRef oStream;

 

// 创建一个可读写的socket连接

 

 

CFStreamCreatePairWithSocket(kCFAllocatorDefault, nativesockethandle, &iStream, &oStream);

 

CFStreamClientContext streamcontext={

0,NULL,NULL,NULL

};

// 注册两种事件！

 

CFReadStreamSetClient(iStream, kCFStreamEventHasBytesAvailable, readStream, &streamcontext);

 

CFReadStreamSetClient(iStream, kCFStreamEventCanAcceptBytes, writeStream, &streamcontext);

 

//加入到循环当中！

 

CFReadStreamScheduleWithRunLoop(iStream, CFRunLoopGetCurrent(),kCFRunLoopCommonModes);

 

CFWriteStreamScheduleWithRunLoop(oStream, CFRunLoopGetCurrent(),kCFRunLoopCommonModes);

 

 

CFReadStreamOpen(iStream);

 

CFWriteStreamOpen(oStream);

}

 

 

}

 

 

 

void readStream(CFReadStreamRef stream,CFStreamEventType eventType, void *clientCallBackInfo) {

 

    UInt8 buff[255];

 

    CFReadStreamRead(stream, buff, 255);

 

    printf("received: %s", buff);

 

}

 

void writeStream (CFWriteStreamRef stream, CFStreamEventType eventType, void *clientCallBackInfo) {

 

   // outputStream = stream;

 

 

 

   char *str = "nihao";

CFWriteStreamWrite(outputStream, str, strlen(line) + 1);

}

 

另一种方法是使用NSStream的方式构建客户端，然后发送和接受内容。

 

 

-(void)startClient

{

    host = [NSHosthostWithAddress:@"192.168.201.24"];//hostWithName:@"www.apple.com"];

    [NSStreamgetStreamsToHost:host port:4242 inputStream:&inStream outputStream:&outStream];

     

    if((inStream == nil) || (outStream == nil))

    {

        NSLog(@"Error: Failed to create streams!") ;

        [selfrelease];

    }

}

 

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

{

    switch(eventCode) {

        caseNSStreamEventHasBytesAvailable:

        {

            NSMutableData*input = [[NSMutableDataalloc] init];

            uint8_t buffer[1024];

            intlen;

            while([inStream hasBytesAvailable])

            {

                len = [inStream read:buffer maxLength:sizeof(buffer)];

                if(len > 0)

                {

                    [input appendBytes:buffer length:len];

                }

            }

            self._resultdata = input;

            self._resultstring = [[NSStringalloc] initWithData:input encoding:NSUTF8StringEncoding];

            [input release];

            break;

        }

        caseNSStreamEventEndEncountered:

            [selfcloseStream];

            break;

        caseNSStreamEventHasSpaceAvailable:

        caseNSStreamEventErrorOccurred:

        {

            NSLog(@"Error:%@:%@",[[aStream streamError] code], [[aStream streamError] localizedDescription]);

        }

        caseNSStreamEventOpenCompleted:

        caseNSStreamEventNone:

        default:

            break;

    }

}

 

-(void)closeStream{

    [inStream close];

    [outStream close];

    [inStream removeFromRunLoop:[NSRunLoopcurrentRunLoop] forMode:NSDefaultRunLoopMode];

    [outStream removeFromRunLoop:[NSRunLoopcurrentRunLoop] forMode:NSDefaultRunLoopMode];

    [inStream setDelegate:nil];

    [outStream setDelegate:nil];

    [inStream release];

    [outStream release];

    inStream = nil;

    outStream = nil;

}

 

-(void)openStream{

    [inStream retain];

    [outStream retain];

    [inStream setProperty:NSStreamSocketSecurityLevelSSLv3forKey:NSStreamSocketSecurityLevelKey];

    [outStream setProperty:NSStreamSocketSecurityLevelSSLv3forKey:NSStreamSocketSecurityLevelKey];

    NSMutableDictionary* sslSettings;

    sslSettings = [NSMutableDictionarydictionaryWithObjectsAndKeys:(id)kCFBooleanFalse,kCFStreamSSLValidatesCertificateChain,kCFBooleanFalse,kCFStreamSSLIsServer,nil];

    CFWriteStreamSetProperty((CFWriteStreamRef)outStream, kCFStreamPropertySSLSettings, sslSettings);

    [inStream setDelegate:self];

    [outStream setDelegate:self];

    [inStream scheduleInRunLoop:[NSRunLoopcurrentRunLoop] forMode:NSDefaultRunLoopMode];

    [outStream scheduleInRunLoop:[NSRunLoopcurrentRunLoop] forMode:NSDefaultRunLoopMode];

    [inStream open];

    [outStream open];

}

 

-(int)writeString: (NSString*) string

{

    NSData*messageAsData = [string dataUsingEncoding:NSASCIIStringEncoding];

    return[outStream write: (c*****t uint8_t *) [messageAsData bytes] maxLength: [messageAsData length]];

}

 

-(int)writeBytes: (char*) buffer length: (unsigned int) len

{

    return[outStream write: (c*****t uint8_t *) buffer maxLength: len];

}

@end