Question

我正在编写一个命令行工具，想要处理各种输入，并且还希望在特定命令上触发Timer（）并在另一个命令上停止它。不幸的是，这不起作用

import Foundation

class timerTest : NSObject {


var myTimer : Timer? = nil
func startTimer() {
    myTimer = Timer.scheduledTimer(withTimeInterval: 1, repeats: true, block: {_ in
        print("Hello")
    })

    let runLoop = RunLoop()
    runLoop.add(myTimer!, forMode: .defaultRunLoopMode)
    RunLoop.current.run()
}

func stopTimer() {
    myTimer?.invalidate()
}


}
var a = timerTest()

print("Ready")

while true {
    var keyboard = FileHandle.standardInput
    var inputData = keyboard.availableData
    var string = NSString(data: inputData, encoding:String.Encoding.utf8.rawValue) as! String
    string = string.trimmingCharacters(in: .whitespacesAndNewlines)
    if string == "timer" { a.startTimer() }
    if string == "stop" { a.stopTimer() }

}

Answer 1

您可以使用以下内容：

import Foundation

var shouldKeepRunning = true

class CLIInput:NSObject {
    var inputTimer:Timer? = nil
    var myTimer:Timer? = nil

    func getInput() {
        inputTimer = Timer.scheduledTimer(withTimeInterval:1, repeats:false, block: {_ in
            var input = readLine()!
            input = input.trimmingCharacters(in: .whitespacesAndNewlines)
            print("Input: \(input)")
            if input == "timer" {
                print("Start timer")
                self.myTimer = Timer.scheduledTimer(withTimeInterval:1, repeats: true, block: {_ in
                    print("Hello")
                })
            }
            if input == "stop" {
                print("Stop timer")
                self.myTimer?.invalidate()
                self.myTimer = nil
            }
            if input == "exit"  {
                print("Time to exit")
                self.inputTimer?.invalidate()
                self.inputTimer = nil
                shouldKeepRunning = false
                return
            }
            // Otherwise, set up timer again
            self.getInput()
        })
    }
}

print("Start")
var cli = CLIInput()
cli.getInput()
let theRL = RunLoop.current
while shouldKeepRunning && theRL.run(mode: .defaultRunLoopMode, before: .distantFuture) { }

但是，无论何时等待标准输入的输入，您都会发现定时器模块输出没有显示，因为输出被阻止直到输入完成。只要你的计时器进程不需要做任何输出，上面可能（或可能不是，取决于你的要求）工作......

在Swift中使用Timer（）的命令行工具

1 个答案: