1、AsyncSocket
基于 CFSocket、GCD 进行的封装（OC）。
支持 TCP 和 UDP。
完整的回调函数（用于处理各种回调事件，连接成功，断开连接，收到数据等）。
需要注意的问题：
- 1、Socekt 连接成功回调方法中主动调用：
[self.socket readDataWithTimeout:-1 tag:0];，相当于主动添加一个读取请求，不然不会执行读取信息回调方法。 - 2、读取信息回调方法中，读取完信息后，主动调用一下
[self.socket readDataWithTimeout:-1 tag:0];，读取完信息后，重新向队列中添加一个读取请求，不然当收到信息后不会执行读取回调方法。
- 1、Socekt 连接成功回调方法中主动调用：
2、基本使用
2.1 Client 客户端
TCP 客户端
#import "GCDAsyncSocket.h" @interface ViewController ()
@property (weak, nonatomic) IBOutlet UITextField *addrTF; @property (weak, nonatomic) IBOutlet UITextField *portTF; @property (weak, nonatomic) IBOutlet UITextField *msgTF; @property (weak, nonatomic) IBOutlet UITextView *logTV; @property (nonatomic, strong) GCDAsyncSocket *clientSockfd; @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; // 创建 Socket，在主队列中处理，所有的回执都在主队列中执行。 self.clientSockfd = [[GCDAsyncSocket alloc] initWithDelegate:self delegateQueue:dispatch_get_main_queue()]; } - (IBAction)connectBtnClick:(id)sender { NSError *error = nil; // Socket 连接 if (![self.clientSockfd isConnected]) { [self.clientSockfd connectToHost:_addrTF.text onPort:_portTF.text.intValue error:&error]; } if (error != nil) { [self showLogMessage:@"连接失败..."]; } } #pragma mark - GCDAsyncSocketDelegate 协议方法 // 连接成功，协议方法 - (void)socket:(GCDAsyncSocket *)sock didConnectToHost:(NSString *)host port:(uint16_t)port { // 读取数据，必须添加，相当于主动添加一个读取请求，不然不会执行读取信息回调方法 [self.clientSockfd readDataWithTimeout:-1 tag:0]; [self showLogMessage:[NSString stringWithFormat:@"连接服务器地址：%@, 端口：%d 成功", host, port]]; [self showLogMessage:[NSString stringWithFormat:@"本地地址：%@, 端口：%d", sock.localHost, sock.localPort]]; } // 已经断开链接，协议方法 - (void)socketDidDisconnect:(GCDAsyncSocket *)sock withError:(NSError *)err { [self showLogMessage:@"socket 断开连接..."]; } // 读取到数据，协议方法 - (void)socket:(GCDAsyncSocket *)sock didReadData:(NSData *)data withTag:(long)tag { // 注意：要想长连接，必须还要在 DidReceiveData 的 delegate 中再写一次 [_udpSocket receiveOnce:&error] // 读取数据，读取完信息后，重新向队列中添加一个读取请求，不然当收到信息后不会执行读取回调方法。 [self.clientSockfd readDataWithTimeout:-1 tag:0]; NSString *strMsg = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]; [self showLogMessage:[NSString stringWithFormat:@"recv：%@", strMsg]]; } #pragma mark - 发送数据 - (IBAction)sendBtnClick:(id)sender { // Socket 发送数据 [self.clientSockfd writeData:[_msgTF.text dataUsingEncoding:NSUTF8StringEncoding] withTimeout:30 tag:0]; [self showLogMessage:[NSString stringWithFormat:@"send：%@", _msgTF.text]]; } // 显示信息 - (void)showLogMessage:(NSString *)msg { _logTV.text = [_logTV.text stringByAppendingFormat:@"%@\n", msg]; } // 键盘回收 - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { [self.view endEditing:YES]; } @end 
2.2 Server 服务端
TCP 服务端
#import
#import #import "GCDAsyncSocket.h" @interface ViewController () @property (weak, nonatomic) IBOutlet UITextField *addrTF; @property (weak, nonatomic) IBOutlet UITextField *portTF; @property (weak, nonatomic) IBOutlet UITextField *msgTF; @property (weak, nonatomic) IBOutlet UITextView *logTV; @property (nonatomic, strong) GCDAsyncSocket *serverSocketfd; @property (nonatomic, strong) GCDAsyncSocket *clientSocketfd; @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; NSString *ip_addr = [self getIPAddress]; _addrTF.text = ip_addr; // 创建 Socket，在主队列中处理，所有的回执都在主队列中执行。 self.serverSocketfd = [[GCDAsyncSocket alloc] initWithDelegate:self delegateQueue:dispatch_get_main_queue()]; } - (IBAction)listenBtnClick:(id)sender { NSError *error = nil; // Socket 监听 [self.serverSocketfd acceptOnPort:_portTF.text.intValue error:&error]; if (error != nil) { NSLog(@"监听出错：%@", error); } else{ [self showLogMessage:@"正在监听..."]; } } #pragma mark - GCDAsyncSocketDelegate 协议方法 // 接收到连接请求，协议方法 - (void)socket:(GCDAsyncSocket *)sock didAcceptNewSocket:(GCDAsyncSocket *)newSocket { // 读取数据，必须添加，相当于主动添加一个读取请求，不然不会执行读取信息回调方法 [newSocket readDataWithTimeout:-1 tag:0]; [self showLogMessage:@"收到客户端连接...."]; [self showLogMessage:[NSString stringWithFormat:@"客户端地址：%@, 端口：%d", newSocket.connectedHost, newSocket.connectedPort]]; self.clientSocketfd = newSocket; } // 已经断开链接，协议方法 - (void)socketDidDisconnect:(GCDAsyncSocket *)sock withError:(NSError *)err { [self showLogMessage:@"socket 断开连接..."]; } // 读取到数据，协议方法 - (void)socket:(GCDAsyncSocket *)sock didReadData:(NSData *)data withTag:(long)tag { // 读取数据，读取完信息后，重新向队列中添加一个读取请求，不然当收到信息后不会执行读取回调方法。 [sock readDataWithTimeout:-1 tag:0]; NSString *strMsg = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]; [self showLogMessage:[NSString stringWithFormat:@"recv：%@",strMsg]]; } #pragma mark - 发送数据 - (IBAction)sendBtnClick:(id)sender { // Socket 发送数据 [self.clientSocketfd writeData:[_msgTF.text dataUsingEncoding:NSUTF8StringEncoding] withTimeout:30 tag:0]; [self showLogMessage:[NSString stringWithFormat:@"send：%@", _msgTF.text]]; } #pragma mark - 获取本地 IP 地址 - (NSString *)getIPAddress { NSString *address = @"error"; struct ifaddrs *interfaces = NULL; struct ifaddrs *temp_addr = NULL; int success = 0; // retrieve the current interfaces - returns 0 on success success = getifaddrs(&interfaces); if (success == 0) { // Loop through linked list of interfaces temp_addr = interfaces; while (temp_addr != NULL) { if (temp_addr->ifa_addr->sa_family == AF_INET) { // Check if interface is en0 which is the wifi connection on the iPhone if ([[NSString stringWithUTF8String:temp_addr->ifa_name] isEqualToString:@"en0"]) { // Get NSString from C String address = [NSString stringWithUTF8String:inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_addr)->sin_addr)]; } } temp_addr = temp_addr->ifa_next; } } // Free memory freeifaddrs(interfaces); return address; } // 显示信息 - (void)showLogMessage:(NSString *)msg { _logTV.text = [_logTV.text stringByAppendingFormat:@"%@\n", msg]; } // 键盘回收 - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { [self.view endEditing:YES]; } @end 
2.3 UDP 通信
UDP 通信
#import
#import #import "GCDAsyncUdpSocket.h" @interface ViewController () @property (weak, nonatomic) IBOutlet UITextField *desAddrTF; @property (weak, nonatomic) IBOutlet UITextField *desPortTF; @property (weak, nonatomic) IBOutlet UITextField *locAddrTF; @property (weak, nonatomic) IBOutlet UITextField *locPortTF; @property (weak, nonatomic) IBOutlet UITextField *msgTF; @property (weak, nonatomic) IBOutlet UITextView *logTV; @property (nonatomic, strong) GCDAsyncUdpSocket *udpSocketfd; @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; NSString *ip_addr = [self getIPAddress]; _locAddrTF.text = ip_addr; // 创建 Socket，在主队列中处理，所有的回执都在主队列中执行 self.udpSocketfd = [[GCDAsyncUdpSocket alloc] initWithDelegate:self delegateQueue:dispatch_get_main_queue()]; } - (IBAction)connectBtnClick:(id)sender { NSError *error = nil; // 绑定端口 [self.udpSocketfd bindToPort:_locPortTF.text.intValue error:&error]; if (error != nil) { NSLog(@"绑定端口出错：%@", error); return; } else{ [self showLogMessage:[NSString stringWithFormat:@"绑定端口 %d 成功...", _locPortTF.text.intValue]]; } // 开始接收数据 [self.udpSocketfd beginReceiving:&error]; if (error != nil) { NSLog(@"开始接收数据出错：%@", error); } else{ [self showLogMessage:@"开始接收数据..."]; } } #pragma mark - GCDAsyncUdpSocketDelegate 协议方法 // 接收到的数据，协议方法 - (void)udpSocket:(GCDAsyncUdpSocket *)sock didReceiveData:(NSData *)data fromAddress:(NSData *)address withFilterContext:(id)filterContext { NSString *strMsg = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]; [self showLogMessage:[NSString stringWithFormat:@"recv：%@", strMsg]]; } #pragma mark - 发送数据 - (IBAction)sendBtnClick:(id)sender { // Socket 发送数据 [self.udpSocketfd sendData:[_msgTF.text dataUsingEncoding:NSUTF8StringEncoding] toHost:_desAddrTF.text port:_desPortTF.text.intValue withTimeout:30 tag:0]; [self showLogMessage:[NSString stringWithFormat:@"send：%@", _msgTF.text]]; } #pragma mark - 获取本地 IP 地址 - (NSString *)getIPAddress { NSString *address = @"error"; struct ifaddrs *interfaces = NULL; struct ifaddrs *temp_addr = NULL; int success = 0; // retrieve the current interfaces - returns 0 on success success = getifaddrs(&interfaces); if (success == 0) { // Loop through linked list of interfaces temp_addr = interfaces; while (temp_addr != NULL) { if (temp_addr->ifa_addr->sa_family == AF_INET) { // Check if interface is en0 which is the wifi connection on the iPhone if ([[NSString stringWithUTF8String:temp_addr->ifa_name] isEqualToString:@"en0"]) { // Get NSString from C String address = [NSString stringWithUTF8String:inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_addr)->sin_addr)]; } } temp_addr = temp_addr->ifa_next; } } // Free memory freeifaddrs(interfaces); return address; } // 显示信息 - (void)showLogMessage:(NSString *)msg { _logTV.text = [_logTV.text stringByAppendingFormat:@"%@\n", msg]; } // 键盘回收 - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { [self.view endEditing:YES]; } @end 
2.4 Socket 长连接
PublicTool.h
@interface PublicTool : NSObject // 字典转换成 JSON 字符串 + (NSString *)JSONStringWithDic:(NSDictionary *)dic; // JSON 字符串转换成字典 + (NSDictionary *)dictionaryWithJSON:(NSString *)json; @end
PublicTool.m
@implementation PublicTool // 字典转成成 JSON 字符串 + (NSString *)JSONStringWithDic:(NSDictionary *)dic { NSError *error = nil; NSData *jsonData = [NSJSONSerialization dataWithJSONObject:dic options:0 error:&error]; if (jsonData == nil) { NSLog(@"fail to get JSON from dictionary: %@, error: %@", self, error); return nil; } NSString *jsonString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding]; return jsonString; } // JSON 字符串转换成字典 + (NSDictionary *)dictionaryWithJSON:(NSString *)json { NSError *error = nil; NSData *jsonData = [json dataUsingEncoding:NSUTF8StringEncoding]; NSDictionary *jsonDict = [NSJSONSerialization JSONObjectWithData:jsonData options:NSJSONReadingMutableContainers | NSJSONReadingAllowFragments error:&error]; if (jsonDict == nil) { NSLog(@"fail to get dictioanry from JSON: %@, error: %@", json, error); return nil; } return jsonDict; } @endSocketSingleTon.h
@interface SocketSingleTon : NSObject @property (nonatomic, copy) NSString *hostAddr; @property (nonatomic, copy) NSString *port; @property (nonatomic, copy) void(^msgLog)(NSString *); + (instancetype)shareInstance; // 连接到服务器 - (void)connectToServer; // 断开连接 - (void)cutOffSocket; // 发送数据到服务器 - (void)sendDataToServer:(NSData*)data; @end
SocketSingleTon.m
#import "GCDAsyncSocket.h" #import
#import #import "PublicTool.h" typedef NS_ENUM(NSInteger, SocketOffline) { SocketOfflineByServer, SocketOfflineByUser }; @interface SocketSingleTon () @property (nonatomic, strong) GCDAsyncSocket *socket; @property (nonatomic, strong) NSTimer *beatTimer; @end @implementation SocketSingleTon + (instancetype)shareInstance { static SocketSingleTon *shareInstance = nil; static dispatch_once_t onceToken; dispatch_once(&onceToken, ^{ shareInstance = [[self alloc] init]; }); return shareInstance; } // 连接到服务器 - (void)connectToServer { NSError *error = nil; if (self.socket != nil) { if ([self.socket isConnected]) { // 断开后再连接 self.socket.userData = @(SocketOfflineByUser); [self cutOffSocket]; [self.socket connectToHost:self.hostAddr onPort:self.port.intValue error:&error]; } else { [self.socket connectToHost:self.hostAddr onPort:self.port.intValue error:&error]; } } else { self.socket = [[GCDAsyncSocket alloc] initWithDelegate:self delegateQueue:dispatch_get_main_queue()]; [self.socket connectToHost:self.hostAddr onPort:self.port.intValue error:&error]; } if (error != nil) { NSLog(@"socket 连接失败：%@", error); } else { NSLog(@"socket 连接成功"); } } // 断开连接 - (void)cutOffSocket { self.socket.userData = @(SocketOfflineByUser); [self.socket disconnect]; } #pragma mark - GCDAsyncSocketDelegate 协议方法 // 连接成功，协议方法 - (void)socket:(GCDAsyncSocket *)sock didConnectToHost:(NSString *)host port:(uint16_t)port { [sock readDataWithTimeout:-1 tag:0]; NSString *logStr = [NSString stringWithFormat:@"连接主机：%@:%d 成功\n", host, port]; NSLog(@"%@", logStr); if (self.msgLog) { self.msgLog(logStr); } // 创建定时器，定时发送 beat 包 self.beatTimer = [NSTimer scheduledTimerWithTimeInterval:5 target:self selector:@selector(longConnectToServer) userInfo:nil repeats:YES]; } // 连接断开，协议方法 - (void)socketDidDisconnect:(GCDAsyncSocket *)sock withError:(NSError *)err { self.socket = nil; [self.beatTimer invalidate]; self.beatTimer = nil; if ([sock.userData isEqual: @(SocketOfflineByUser)]) { NSLog(@"the socket have been cutted off by user"); if (self.msgLog) { self.msgLog(@"the socket have been cutted off by user"); } } else if (sock.userData == SocketOfflineByServer) { NSLog(@"the socket have been cutted off by server"); if (self.msgLog) { self.msgLog(@"the socket have been cutted off by server"); } // reconnect [self connectToServer]; } else { NSLog(@"%@", err.localizedDescription); if (self.msgLog) { self.msgLog([NSString stringWithFormat:@"%@", err.localizedDescription]); } [self connectToServer]; } } // 收到消息，协议方法 - (void)socket:(GCDAsyncSocket *)sock didReadData:(NSData *)data withTag:(long)tag { [sock readDataWithTimeout:-1 tag:0]; char buf[1024]; [data getBytes:buf length:1024]; NSString *receivedData = [NSString stringWithCString:buf encoding:NSUTF8StringEncoding]; NSLog(@"receivedData：%@", [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]); if (receivedData.length > 0) { NSDictionary *dataDic = [PublicTool dictionaryWithJSON:receivedData]; if ([dataDic[@"msgType"] isEqualToString:@"beta"]) { NSString *strMsg = [NSString stringWithFormat:@"收到心跳确认的数据：%@\n", receivedData]; if (self.msgLog) { self.msgLog(strMsg); } } else if ([dataDic[@"msgType"] isEqualToString:@"normal"]) { NSString *strMsg = [NSString stringWithFormat:@"收到正常的数据：%@\n", receivedData]; if (self.msgLog) { self.msgLog(strMsg); } } else if ([dataDic[@"msgType"] isEqualToString:@"exit"]) { NSString *strMsg = [NSString stringWithFormat:@"收到关闭的数据：%@\n", receivedData]; if (self.msgLog) { self.msgLog(strMsg); } [self cutOffSocket]; } } } // 发送数据 - (void)longConnectToServer { [self sendDataToServer:[@"hello" dataUsingEncoding:NSUTF8StringEncoding]]; } // 发送数据到服务器 - (void)sendDataToServer:(NSData*)data { NSString *dataStr = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]; NSMutableDictionary *dicParams = [NSMutableDictionary dictionary]; if ([dataStr isEqualToString:@"hello"]) { [dicParams setValue:dataStr forKey:@"msg"]; [dicParams setValue:@"beta" forKey:@"msgType"]; } else { [dicParams setValue:dataStr forKey:@"msg"]; [dicParams setValue:@"normal" forKey:@"msgType"]; } NSData *sendData = [[PublicTool JSONStringWithDic:dicParams] dataUsingEncoding:NSUTF8StringEncoding]; NSString *strMsg = [NSString stringWithFormat:@"发送数据: %@\n", [PublicTool JSONStringWithDic:dicParams]]; if (self.msgLog) { self.msgLog(strMsg); } [self.socket writeData:sendData withTimeout:30 tag:0]; } @end ViewController.m
#import "SocketSingleTon.h" #import "PublicTool.h" @interface ViewController () @property (weak, nonatomic) IBOutlet UITextField *addressTF; @property (weak, nonatomic) IBOutlet UITextField *portTF; @property (weak, nonatomic) IBOutlet UITextField *msgTF; @property (weak, nonatomic) IBOutlet UITextView *logTV; @end @implementation ViewController - (IBAction)connectToServer:(id)sender { // 创建 Socket SocketSingleTon *socketInstance = [SocketSingleTon shareInstance]; socketInstance.hostAddr = _addressTF.text; socketInstance.port = _portTF.text; __weak __typeof (self)weakSelf = self; socketInstance.msgLog = ^(NSString *log){ dispatch_async(dispatch_get_main_queue(), ^{ weakSelf.logTV.text = [weakSelf.logTV.text stringByAppendingString:log]; }); }; // 连接到服务器 [socketInstance connectToServer]; } - (IBAction)cutOffConnect:(id)sender { SocketSingleTon *socketInstance = [SocketSingleTon shareInstance]; // 断开连接 [socketInstance cutOffSocket]; } - (IBAction)sendDataToServer:(id)sender { SocketSingleTon *socketInstance = [SocketSingleTon shareInstance]; // 发送数据到服务器 [socketInstance sendDataToServer:[_msgTF.text dataUsingEncoding:NSUTF8StringEncoding]]; } - (IBAction)sendBetaDataToServer:(id)sender { SocketSingleTon *socketInstance = [SocketSingleTon shareInstance]; NSMutableDictionary *dicParams = [NSMutableDictionary dictionary]; [dicParams setValue:@"beta" forKey:@"msgType"]; [dicParams setValue:@"hello" forKey:@"msg"]; NSString *strMsg = [PublicTool JSONStringWithDic:dicParams]; // 发送心跳数据到服务器 [socketInstance sendDataToServer:[strMsg dataUsingEncoding:NSUTF8StringEncoding]]; } - (IBAction)clearLog:(id)sender { _logTV.text = nil; } // 键盘回收 - (void)touchesBegan:(NSSet*)touches withEvent:(UIEvent *)event { [self.view endEditing:YES]; } @end 