Swift socket.io .emit（）不会触发

Question

I'm new to sockets and i'm stuck with the following problem, i use this library to connect my app to my nodejs server. I'd like to know why if i call socket.emit() in the following way doesn't work:

override func viewDidLoad() {
    var socket: SocketIOClient = SocketIOClient(socketURL: NSURL(string: "myhosturl")!)

    socket.emit("ping","some data");
    socket.connect();
}

It doesn't work neither swiping socket.emit and socket.connect functions but if I trigger the socket.emit function by clicking a button it works:

override func viewDidLoad() {
   var socket: SocketIOClient = SocketIOClient(socketURL: NSURL(string: "myhosturl")!)
   socket.connect();
}

@IBAction func sendMessage(sender: AnyObject) {
   socket.emit("ping","some data");
}

I think i'm missing something here, it would be great is someone could explain this to me

Answer 1

Sockets require a connection before emit is called. You should probably wait until there is a connection before u emit. Try this:

override func viewDidLoad() {
    let socket = SocketIOClient(socketURL: NSURL(string: "myhosturl")!)
    socket.on("connect") { _, _ in
        print("socket connected")
        socket.emit("ping", "data")
    }
    socket.on("ping") { _, _ in
        print("ping received")
    }
    socket.connect()
}