庫地址：https://github.com/socketio/socket.io-client-swift

OC版:

@import SocketIO;

@property (nonatomic, strong) SocketIOClient *socket;

@property (nonatomic, copy) NSString *mySendString;//發(fā)送內容 
@property (nonatomic, copy) NSString *myLoginName;//發(fā)送方
@property (nonatomic, copy) NSString *receiverName;//接收方

- (void)viewDidLoad {
    [super viewDidLoad];
    [self connectSocket];
}

/**
 連接Socket
 */
- (void)connectSocket {
    NSURL* url = [[NSURL alloc] initWithString:@"http://localhost:8080"];//僅舉例，寫自己項目的接口
    SocketManager* manager = [[SocketManager alloc] initWithSocketURL:url config:@{@"log": @YES, @"compress": @YES}];
    SocketIOClient* socket = manager.defaultSocket;    

    //監(jiān)聽連接Socket連接是否成功
    [socket on:@"connect" callback:^(NSArray* data, SocketAckEmitter* ack) {
        NSLog(@"socket connected==%@",data);
    }];
    
    //chat message2 為 監(jiān)聽接收消息 的方法名(為舉例)  與后臺協(xié)定方法名 
    [socket on:@"chat message2" callback:^(NSArray* data, SocketAckEmitter* ack) {
        [self receiveMessage: data];
        NSLog(@"接收到了:%@", data);
    }];
    
    self.socket = socket;
    
    [socket connect];
}

/**
 發(fā)送消息
 @param text 發(fā)送內容
 */
- (void)sendMessage:(NSString *)text {
    NSLog(@"發(fā)送消息");
    //發(fā)送消息，包括發(fā)送方、接收方、發(fā)送內容
    //例如：
    NSString *cur = [NSString stringWithFormat:@"%@?%%?%%%@*%%*%%%@",receiverName,text,myLoginName];

    mySendString = cur;
    
    //發(fā)送消息socket   
    //chat message 為發(fā)送消息給后臺的方法名 (為舉例)  與后臺協(xié)定方法名
    [self.socket emit:@"chat message" with:@[cur]];
}

/**
 接收到消息
 
 @param data 消息內容
 */
- (void)receiveMessage:(NSArray *)data {
 
    NSString *receiveStr = data[0];
    
    if (![mySendString isEqualToString:receiveStr]) {
        
        NSString *str = data[0];
        NSArray *array = [str componentsSeparatedByString:@"?%?%"];
        
        NSString *str1 = array[1];
        NSArray *array1 = [str1 componentsSeparatedByString:@"*%*%"];
        
        if ([array[0] isEqualToString:_loginName]) {
            //消息添加并展示
        }
        NSLog(@"內容內容:%@",array1[0]);
    }else {
        NSLog(@"自己發(fā)送的消息，不用處理");
    }
    
    NSLog(@"全部內容:%@, %@",data[0], data);
}

swift版:

import SocketIO

var socket: SocketIOClient?

//發(fā)送內容 
var mySendString = ""
//發(fā)送方
var myLoginName = ""
//接收方
var receiverName = ""

override func viewDidLoad() {
    super.viewDidLoad()
    connectSocket()
}

/**
 連接Socket
 */
private func connectSocket() {
    let url = URL(string: "http://localhost:8080") //僅舉例，寫自己項目的接口
    let manager = SocketManager(socketURL: url, config: ["log": true, "compress": true])
    let socket: SocketIOClient? = manager.defaultSocket
    //監(jiān)聽連接Socket連接是否成功
    socket?.on("connect", callback: {(_ data: [Any]?, _ ack: SocketAckEmitter?) -> Void in
        print("socket connected==\(data ?? "")")
    })
    //chat message2 為 監(jiān)聽接收消息 的方法名(為舉例)  與后臺協(xié)定方法名  
    socket?.on("chat message2", callback: {(_ data: [Any]?, _ ack: SocketAckEmitter?) -> Void in
        self.receiveMessage(data)
        print("接收到了:\(data ?? "")")
    })
    self.socket = socket
    socket?.connect()
}

/**
 發(fā)送消息
 @param text 發(fā)送內容
 */
private func sendMessage(_ text: String?) {
    print("發(fā)送消息")
        //發(fā)送消息，包括發(fā)送方、接收方、發(fā)送內容
        //例如：
    let cur = "\(receiverName)?%%?%%\(text ?? "")*%%*%%\(myLoginName)"
    mySendString = cur
    //發(fā)送消息socket
    //chat message 為發(fā)送消息給后臺的方法名 (為舉例)  與后臺協(xié)定方法名
    socket.emit("chat message", with: [cur])
}

/**
 接收到消息
 @param data 消息內容
 */
private func receiveMessage(_ data: [Any]?) {
    let receiveStr = data[0] as? String
    if !(mySendString == receiveStr) {
        let str = data[0] as? String
        let array = str?.components(separatedBy: "?%?%")
        let str1 = array[1]
        let array1 = str1.components(separatedBy: "*%*%")
        if (array[0] == loginName) {
            //消息添加并展示
        }
        print("內容內容:\(array1[0])")
    } else {
        print("自己發(fā)送的消息，不用處理")
    }
    print("全部內容:\(data[0]), \(data ?? "")")
}

PS:
由于socket.io-client-swift為swift庫，如果項目是用OC語言開發(fā)的，需進行橋接才能使用
參考：iOS混編