NSTimer、NSTask、NSThread 和 NSRunloop 之间的基本区别是什么

NSTimer、NSTask、NSThread 和 NSRunloop 是 iOS 开发中常用的四种多线程处理方式，它们有着不同的特点和用途。下面将详细介绍这四种多线程处理方式的基本区别。

swift
class ViewController: UIViewController {
    var timer: Timer?
    override func viewDidLoad() {
        super.viewDidLoad()
        timer = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(updateTimer), userInfo: nil, repeats: true)
    }
    @objc func updateTimer() {
        // 定时执行的方法
    }
    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        timer?.invalidate()
        timer = nil
    }
}

swift
let task = Process()
task.launchPath = "/bin/sh"
task.arguments = ["-c", "echo Hello World"]
let pipe = Pipe()
task.standardOutput = pipe
task.launch()
let data = pipe.fileHandleForReading.readDataToEndOfFile()
if let output = String(data: data, encoding: .utf8) {
    print(output)
}

swift
let thread = Thread {
    // 在子线程中执行的代码逻辑
    for i in 0..<10 {
        print("Count: \(i)")
        sleep(1)
    }
}
thread.start()

swift
func runThread() {
    autoreleasepool {
        let runloop = RunLoop.current
        let timer = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(updateTimer), userInfo: nil, repeats: true)
        runloop.add(timer, forMode: .default)
        runloop.run()
    }
}
@objc func updateTimer() {
    // 定时执行的方法
}