如何使用CFNetwork从套接字获取字节数组?
问题描述:
我正在为iPad项目工作,它是一个小程序,我需要它与另一个在Windows上运行并且像服务器一样运行的软件进行通信;所以我为iPad创建的应用程序将是客户端。如何使用CFNetwork从套接字获取字节数组?
我使用CFNetwork的做插座的沟通,这是我建立连接方式:
char ip[] = "192.168.0.244";
NSString *ipAddress = [[NSString alloc] initWithCString:ip];
/* Build our socket context; this ties an instance of self to the socket */
CFSocketContext CTX = { 0, self, NULL, NULL, NULL };
/* Create the server socket as a TCP IPv4 socket and set a callback */
/* for calls to the socket's lower-level connect() function */
TCPClient = CFSocketCreate(NULL, PF_INET, SOCK_STREAM, IPPROTO_TCP, kCFSocketDataCallBack, (CFSocketCallBack)ConnectCallBack, &CTX);
if (TCPClient == NULL)
return;
/* Set the port and address we want to listen on */
struct sockaddr_in addr;
memset(&addr, 0, sizeof(addr));
addr.sin_len = sizeof(addr);
addr.sin_family = AF_INET;
addr.sin_port = htons(PORT);
addr.sin_addr.s_addr = inet_addr([ipAddress UTF8String]);
CFDataRef connectAddr = CFDataCreate(NULL, (unsigned char *)&addr, sizeof(addr));
CFSocketConnectToAddress(TCPClient, connectAddr, -1);
CFRunLoopSourceRef sourceRef = CFSocketCreateRunLoopSource(kCFAllocatorDefault, TCPClient, 0);
CFRunLoopAddSource(CFRunLoopGetCurrent(), sourceRef, kCFRunLoopCommonModes);
CFRelease(sourceRef);
CFRunLoopRun();
这是我发送的数据,这基本上是一个字节数组
方式/* The native socket, used for various operations */
// TCPClient is a CFSocketRef member variable
CFSocketNativeHandle sock = CFSocketGetNative(TCPClient);
Byte byteData[3];
byteData[0] = 0;
byteData[1] = 4;
byteData[2] = 0;
send(sock, byteData, strlen(byteData)+1, 0);
最后,你可能已经注意到,当我创建服务器套接字时,我注册了一个kCFSocketDataCallBack类型的回调函数,这是代码。
void ConnectCallBack(CFSocketRef socket, CFSocketCallBackType type, CFDataRef address, const void *data, void *info)
{
// SocketsViewController is the class that contains all the methods
SocketsViewController *obj = (SocketsViewController*)info;
UInt8 *unsignedData = (UInt8 *) CFDataGetBytePtr(data);
char *value = (char*)unsignedData;
NSString *text = [[NSString alloc]initWithCString:value length:strlen(value)];
[obj writeToTextView:text];
[text release];
}
其实,这个回调被在我的代码调用,问题是,我不知道我怎样才能使Windows客户端发过来的数据,我希望接收的字节数组,但我不知道如何从数据参数中获取这些字节。
如果有人可以帮助我找到一个方法来做到这一点,也许我点我另一种方式来从服务器获取数据在我的客户端应用程序,我真的很感激。
谢谢。
答
在您的回调中,data
参数确实为kCFSocketDataCallBack
回调类型的CFDataRef
值。
CFDataRef dataRef = (CFDataRef) data;
Byte *array = new Byte[CFDataGetLength(dataRef)]; // Or use a fixed length
CFDataGetBytes(dataRef, CFRangeMake(0, CFDataGetLength(theData)), array);
array
将包含字节数组。