Question

我有以下连接TCP套接字的功能（Raspberry Pi上的服务器，我通过接入点直接连接）

func connect (host: String, port: Int) {
    Stream.getStreamsToHost(withName: addr, port: port, inputStream: &inputStream, outputStream: &outputStream)
    if outputStream != nil && inputStream != nil {
        outputStream!.delegate = self
        inputStream!.delegate = self
        outputStream!.schedule(in: .main, forMode: RunLoopMode.defaultRunLoopMode)
        inputStream!.schedule(in: .main, forMode: RunLoopMode.defaultRunLoopMode)
        outputStream!.open()
        inputStream!.open()
    }
}

当我连接到Raspberry Pi的Wifi-Hotspot后，委托方法被调用，我可以开始写数据了：

func stream(_ aStream: Stream, handle eventCode: Stream.Event) {
    if aStream === inputStream {
        switch eventCode {
        case Stream.Event.errorOccurred:
            print("input: ErrorOccurred: \(aStream.streamError?.localizedDescription)")
            self.Label.text = "Disconnected"
        case Stream.Event.openCompleted:
            print("input: OpenCompleted")
        case Stream.Event.hasBytesAvailable:
            print("input: HasBytesAvailable")
            // Here you can `read()` from `inputStream`

        default:
            break
        }
    }
    else if aStream === outputStream {
        switch eventCode {
        case Stream.Event.errorOccurred:
            print("output: ErrorOccurred: \(aStream.streamError?.localizedDescription)")
            self.Label.text = "Disconnected"
        case Stream.Event.openCompleted:
            print("output: OpenCompleted")
        case Stream.Event.hasSpaceAvailable:
            // print("output: HasSpaceAvailable")
            // Here you can write() to `outputStream`
            self.write(f: l)
            self.write(f: r)
        default:
            break
        }
    }
}

但是当我连接到另一台WiFi时，这种方法不会被调用。我怎么能检测到这个方法没有被调用，所以我可以提醒用户他没有连接，他应该再次尝试连接？

检查是否调用了委托方法

0 个答案: