iPhone模拟器-模拟一个慢速连接？

import UIKit
import Reachability

class ViewController: UIViewController {

    let reachability = try! Reachability()

    override func viewDidLoad() {
        super.viewDidLoad()
        
        reachability.whenReachable = { [weak self] reachability in
            if reachability.connection == .wifi {
                print("Reachable via WiFi")
            } else {
                print("Reachable via Cellular")
            }
        }
        reachability.whenUnreachable = { _ in
            print("Not reachable")
        }
        
        do {
            try reachability.startNotifier()
        } catch {
            print("Unable to start notifier")
        }
    }
}