xcode中的背景模式（swift）

Question

我是初学程序员（swift -ios 8） 如何刷新我在后台（每5秒）的功能在swift中 我究竟需要什么？

由于

Answer 1

我认为你需要这个：

dispatch_async(dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), { () -> Void in

        //add your function here which will run in background like fetching data from server 
})

修改

如果您想以固定的时间间隔运行任何功能，可以这样使用NSTimer：

var timer = NSTimer.scheduledTimerWithTimeInterval(5, target: self, selector: Selector("yourMethod"), userInfo: nil, repeats: true)

并添加其辅助方法：

//this will repeat on every 5 second
func yourMethod(){
    //your code
}

Answer 2

    func testtcpclient(){

        var client:TCPClient = TCPClient(addr:"46.143.211.41", port:8080)

        var (success,errmsg)=client.connect(timeout: 1)
        if success{

            var (success,errmsg)=client.send(str:"AEBCD1" )
            if success{

                var data=client.read(1024*10)
                if let d=data{
                    if let str=String(bytes: d, encoding: NSUTF8StringEncoding){
                        println(str)



                    }
                }
            }else{


                println(errmsg)
                var alert = UIAlertView()
                alert.title = "no"
                alert.message = "no"
                alert.addButtonWithTitle("ok")
                alert.show()
            }
        }else{
            println(errmsg)
            var alert = UIAlertView()
            alert.title = "no"
            alert.message = "no"
            alert.addButtonWithTitle("ok")
            alert.show()
        }



    }


     var timer = NSTimer.scheduledTimerWithTimeInterval(2, target: self, selector: Selector("testtcpclient"), userInfo: nil, repeats: true)




}