1、網絡編程 CFSocketRefCFSocketCreateCreates a CFSocket object of a specified protocol and type. CFSocketRef CFSocketCreate (CFAllocatorRef allocator,SInt32 protocolFamily, SInt32 socketType, SInt32 protocol, CFOptionFlags callBackTypes, CFSocketCallBack callout, const CFSocketContext *context );- (void)se

2、tTextInMainThread:(NSString *)text NSRange endRange;endRange.location = chatController.textView.text length;endRange.length = textlength;chatController.textView.text= chatController.textView.text stringByAppendingString:server: stringByAppendingString:text;chatController.textView scrollRangeToVisibl

3、e:endRange;- (void)readStreamchar buffer255;NSAutoreleasePool * pool = NSAutoreleasePoolallocinit;while (recv(CFSocketGetNative(_socket),buffer, sizeof(buffer),0) NSString *s = NSString stringWithUTF8String:buffer;self performSelectorOnMainThread:selector(setTextInMainThread :)withObject:s waitUntil

4、Done:YES;pool release;staticvoid TCPServerConnectCallBack(CFSocketRef socket, CFSocketCallBackType type,CFDataRef address, const void *data, void *info) if (data !=NULL) UIAlertView *alert = UIAlertView alloc initWithTitle:message:連接失敗”delegate:nil cancelButtonTitle: 關閉 otherButtonTitles:nil;alert s

5、how;alertrelease;return;TCPClientDemoAppDelegate *delegate = (TCPClientDemoAppDelegate *)info;delegate performSelectorInBackground:selector(readStream) withObject:nil;delegate.connController dismissModalViewControllerAnimated:YES;NSNotificationCenter defaultCenter addObserver:delegate.chatController

6、 selector:selector(keyboardWillShown:) name:UIKeyboardWillShowNotification object:nil;NSNotificationCenter defaultCenter addObserver:delegate.chatControllerselector:selector(keyboardWillHidden:) name:UIKeyboardWillHideNotification object:nil;- (void) doConnect / CFSocketContext 存放一些 CFSocketRef 的相關信

7、息CFSocketContext CTX = 0,self, NULL,NULL, NULL;/ CFSocketCreate 函數是用來創建一個CFSocketRef ，第一個參數是表示由系統默認的 allocator 來為 CFSocketRef 分配一個內存空間。/ 第二個參數表示profocolFamily (協議簇)/ 第三個參數表示 socketType（ socket 的類型流、數據段、 順序包 .）/ 第四個參數表示protocol (協議 tcp、udp.)/ 第五個參數表示當 socket 的某個類型 activity 時，調用第 六個參數的函數/ 第六個參數表示當 soc

8、ket 發生第五個參數的類型的動作 時，調用的函數/ 第七個參數表示一個保存CFSocket object 對象的一些相關信息_socket = CFSocketCreate(kCFAllocatorDefault,PF_INET, SOCK_STREAM,IPPROTO_TCP, kCFSocketConnectCallBack, TCPServerConnectCallBack, &CTX);if (NULL =_socket) UIAlertView *alert = UIAlertView alloc initWithTitle:message:創建套接字失敗”delegate

9、:nil cancelButtonTitle: 關閉 otherButtonTitles:nil;alert show;alertrelease;/ sockaddr_in 是一個 struct，里面包含 ip、端口等 struct sockaddr_in addr4;memset(&addr4,0, sizeof(addr4);/ memset 表示將地址 addr4 結構里面的前sizeof ()個內存地址里面的內容設置成intoaddr4.sin_len =sizeof(addr4);addr4.sin_family =AF_INET;addr4.sin_port =htons(

10、12345);addr4.sin_addr.s_addr = inet_addr(connController.textField.textUTF8String);/ CFDataCreate() 是用來將一個申請一個 sizeof() 大小的內存空間，并將一個 buffer 中的數據拷貝到新申請的 內存空間中CFDataRef address =CFDataCreate(kCFAllocatorDefault, (UInt8 *)&addr4, sizeof(addr4);CFSocketConnectToAddress(_socket, address,-1);CFRunLoopR

11、ef cfrl = CFRunLoopGetCurrent();CFRunLoopSourceRef source =CFSocketCreateRunLoopSource(kCFAllocatorDefault, _socket,0);CFRunLoopAddSource(cfrl, source,kCFRunLoopCommonModes);CFRelease(source);- (void) sendMessage NSString *stringToSend = chatController.textField.textstringByAppendingString:n;constch

12、ar *data = stringToSendUTF8String;send(CFSocketGetNative(_socket), data,strlen(data) + 1,0);NSRange endRange;endRange.location = chatController.textView.text length;endRange.length = stringToSendlength;chatController.textView.text= chatController.textView.text stringByAppendingString:me: stringByApp

13、endingString:stringToSend;chatController.textView scrollRangeToVisible:endRange;chatController.textField.text = ;recv(), recvfrom()Receive data on a socketPrototypes#include <sys/types.h> #include <sys/socket.h> ssize_t recv(int s, void *buf, size_t len, int flags); ssize_t recvfrom(int

14、s, void *buf, size_t len, int flags, struct sockaddr *from, socklen_t *fromlen);DescriptionOnce you have a socket up and connected, you can read incoming data from the remote side using the recv()(for TCP SOCK_STREAM sockets) and recvfrom() (for UDP SOCK_DGRAM sockets).Both functions take the socket

15、 descriptor s, a pointer to the buffer buf, the size (in bytes) of the buffer len, and a set of flags that control how the functions work.Additionally, the recvfrom() takes a struct sockaddr*, from that will tell you where the data came from, and will fill in fromlen with the size of struct sockaddr

16、. (You must also initialize fromlen tobe the size offrom or struct sockaddr.)So what wondrous flags can you pass into this function? Here are some of them, but you should check your local man pages for more information and what is actually supported on your system. You bitwise-or these together, or

17、just set flags to 0 if you want it to be a regular vanilla recv().MSG_OOBReceive Out of Band data. This is how to get data that has been sent to you with the MSG_OOB flag in send(). As the receiving side, you will have had signal SIGURG raised telling you there is urgent data. In your handler for th

18、at signal, you could call recv() with this MSG_OOB flag.MSG_PEEKIf you want to call recv() just for pretend, you can call it with this flag. This will tell you whats waiting in the buffer for when you call recv() for real (i.e. without the MSG_PEEK flag. Its like a sneak preview into the nextrecv() call.