UserDefaults的切换语句（Swift-Xcode）

Question

我想知道如何为用户默认设置执行switch-case /任何好的声明而不是使用if-else，因为从我的代码中可以看出，我使用3 if语句来升级多余和丑陋。 这个视图控制器的目的是为了一个＆＃34;选择一张卡＆＃34;在游戏中，用户每次都可以选择3张牌，如果他/她选择了一张牌，他们将无法再次选择该牌。

import UIKit

class ViewController: UIViewController {
    @IBOutlet var buttona: UIButton!
    @IBOutlet var buttonb: UIButton!
    @IBOutlet var buttonc: UIButton!

    override func viewDidLoad() {
       super.viewDidLoad()
       if (UserDefaults.standard.integer(forKey: "dissapear") == 1)
       {
           buttona.setImage(UIImage(named: "wildcardbackingblack.png"), for: .normal)
           buttona.isEnabled = false
       }

       if (UserDefaults.standard.integer(forKey: "dissapear2") == 1)
       {
           buttonb.setImage(UIImage(named: "wildcardbackingblack.png"), for: .normal)
           buttonb.isEnabled = false
       }

       if (UserDefaults.standard.integer(forKey: "dissapear3") == 1)
       {
           buttonc.setImage(UIImage(named: "wildcardbackingblack.png"), for: .normal)
           buttonc.isEnabled = false
       }
   }

   override func didReceiveMemoryWarning() {
      super.didReceiveMemoryWarning()
      // Dispose of any resources that can be recreated.
   }

   @IBAction func Button1(_ sender: Any) {
      UserDefaults.standard.set(1, forKey:"dissapear")
      self.performSegue(withIdentifier: "show", sender: nil)         
   }

   @IBAction func Button2(_ sender: Any) {
      UserDefaults.standard.set(1, forKey:"dissapear2")
      self.performSegue(withIdentifier: "show", sender: nil)
   }

   @IBAction func Button3(_ sender: Any) {
      UserDefaults.standard.set(1, forKey:"dissapear3")
      self.performSegue(withIdentifier: "show", sender: nil)
    }
 }

Answer 1

    func updateCard(button: UIButton, image: String, isEnabled: Bool) {
        DispatchQueue.main.asyc {
            button.setImage(UIImage(named:image), for: .normal)
            button.isEnabled = isEnabled
        }
    }

    .
    .
    .

    let option : Int = UserDefaults.standard.integer(forKey: "dissapear")
    switch (option) {
        case 1:
            self.updateCard(button: ..., image:"wildcardbackingblack.png", isEnabled: false)
        case 2:                       
            self.updateCard(button: ..., image:"wildcardbackingblack.png", isEnabled: false)
        case 3:
            self.updateCard(button: ..., image:"wildcardbackingblack.png", isEnabled: false)
        default:
            self.updateCard(button: ..., image:"default.png", isEnabled: false)
    } 
//Save the different integer value in same key user defaults.

 @IBAction func Button1(_ sender: Any) {
      UserDefaults.standard.set(1, forKey:"dissapear")
      self.performSegue(withIdentifier: "show", sender: nil)         
   }

   @IBAction func Button2(_ sender: Any) {
      UserDefaults.standard.set(2, forKey:"dissapear")
      self.performSegue(withIdentifier: "show", sender: nil)
   }

   @IBAction func Button3(_ sender: Any) {
      UserDefaults.standard.set(3, forKey:"dissapear")
      self.performSegue(withIdentifier: "show", sender: nil)
    }

Answer 2

如果我坚持使用相同的UserDefaults存储，我将如何编写此代码。注意：您需要将cardPressed(_:)重新连接到每个按钮/卡

import UIKit

class ViewController: UIViewController {
    @IBOutlet var buttonA: UIButton!
    @IBOutlet var buttonB: UIButton!
    @IBOutlet var buttonC: UIButton!

    let buttonKeyPairs: [(button: UIButton, key: String)] = [
        (buttonA, "dissapear"),
        (buttonB, "dissapear2"),
        (buttonC, "dissapear3"),
    ]

    override func viewDidLoad() {
        super.viewDidLoad()

        for (button, key) in buttonKeyPairs
            where UserDefaults.standard.integer(forKey: key) == 1 {

            button.setImage(UIImage(named: "wildcardbackingblack.png"), for: .normal)
            button.isEnabled = false
        }
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    @IBAction func buttonPressed(_ sender: UIButton) {
        let key: String
        switch UIButton {
            case buttonA: key = "dissapear"
            case buttonB: key = "dissapear2"
            case buttonC: key = "dissapear3"
        }
        UserDefaults.standard.set(1, forKey: key)
        self.performSegue(withIdentifier: "show", sender: self)         
    }
}