＃8 終極密碼

終極密碼是很多人都會玩的遊戲，這次做個小改動，可以自己加入範圍

先拉好textflied和button、label、圖片和背景圖片

終極密碼

輸入範圍的button

這邊??的意思是：將textflied裡面string為nil時，變成空字串，外面再將字串換為int

Swift 特別發明了即使 nil 也能變出預設值的雙重問號。在雙重問號的左邊接 optional 變數(常數)，右邊接預設值，當 optional 不為 nil 時，即解開它的包裝取值。而當 optional 為 nil 時，則回傳預設值。

  @IBAction func enterrange(_ sender: UIButton) {
        minNum = Int(range1.text ?? "") ?? 0
        maxNum = Int(range2.text ?? "") ?? 0
        randomNumber = Int.random(in: minNum!...maxNum!)    }

確認的button

 @IBAction func enter(_ sender: UIButton) {
        let guessNum = Int(number.text ?? "") ?? 0
        if randomNumber == nil {
            answer.text = "請確定數字範圍並按下確定按鈕！！！"
            return
        }
 if guessNum < randomNumber! {
            minNum = guessNum
            answer.text = ("太小了，再試一次！範圍:\(minNum!)~\(maxNum!)")
            number.text = ""
        } else if guessNum > randomNumber! {
            maxNum = guessNum
            answer.text = ("太大了，再試一次！\n範圍:\(minNum!)~\(maxNum!)")
            number.text = ""

        } else {answer.text = ("恭喜你猜中了！")
                   }
        view.endEditing(true)
    }

重玩的button

 @IBAction func restgame(_ sender: UIButton) {
        randomNumber = Int.random(in: minNum!...maxNum!)
        number.text = ""
        answer.text = ""
        range1.text = ""
        range2.text = ""
    }

完整程式碼

import UIKit

class ViewController: UIViewController {
    
    
    
    @IBOutlet weak var number: UITextField!
    
    @IBOutlet weak var answer: UILabel!
    
    @IBOutlet weak var range1: UITextField!
    
    @IBOutlet weak var range2: UITextField!
    
     
    var randomNumber :Int?
    var minNum: Int?
    var maxNum: Int?
     
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
       
    }
    
    @IBAction func enterrange(_ sender: UIButton) {
        minNum = Int(range1.text ?? "") ?? 0
        maxNum = Int(range2.text ?? "") ?? 0
        randomNumber = Int.random(in: minNum!...maxNum!)    }
    
    @IBAction func enter(_ sender: UIButton) {
        let guessNum = Int(number.text ?? "") ?? 0
        if randomNumber == nil {
            answer.text = "請確定數字範圍並按下確定按鈕！！！"
            return
        }
        if guessNum < randomNumber! {
            minNum = guessNum
            answer.text = ("太小了，再試一次！範圍:\(minNum!)~\(maxNum!)")
            number.text = ""
        } else if guessNum > randomNumber! {
            maxNum = guessNum
            answer.text = ("太大了，再試一次！\n範圍:\(minNum!)~\(maxNum!)")
            number.text = ""

        } else {answer.text = ("恭喜你猜中了！")
                   }
        view.endEditing(true)
    }
    
    
    
    @IBAction func restgame(_ sender: UIButton) {
        randomNumber = Int.random(in: minNum!...maxNum!)
        number.text = ""
        answer.text = ""
        range1.text = ""
        range2.text = ""
    }
   
}

GitHub - gawer521n52/-