线程1：EXC_BAD_INSTRUCTION（code = EXC_I386_INVOP）错误

Question

我是Xcode和idk的新手为什么我有这个错误，有人可以帮助我吗？非常感激。这基本上是让用户输入他们给出的验证码，它会根据特定的代码显示一条消息。

VerificationController

import UIKit 

class VerificationController: UIViewController { 

    @IBOutlet var verification: UITextField! 
    @IBAction func enter(_ sender: Any) { 

      if verification.text != "" 
      { 
       if verification.text == "123" 
       { 
        performSegue(withIdentifier: "segue", sender: self) 

       } 
       else if verification.text == "234" 
       { 
        performSegue(withIdentifier: "segue", sender: self) 
       } 
      } 
     } 

    override func viewDidLoad() { 
     super.viewDidLoad() 

     // Do any additional setup after loading the view. 
    } 

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

} 

SecondController

import UIKit 

class SecondViewController: UIViewController { 

    @IBOutlet var label: UILabel! 

    var myString1 = "Hello 123" 
    var myString2 = "Hello 234" 



    override func viewDidLoad() { 
     super.viewDidLoad() 
     if (VerificationController().verification.text! == "123") 
      { 
       label.text = myString1 
      } 
     else if (VerificationController().verification.text! == "234") 
      { 
       label.text = myString2 
      } 


     // Do any additional setup after loading the view. 
    } 

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

[IMAGE OF ERROR]

Answer 1

您需要通过验证文本到SecondViewController在准备（forSegue）方法和访问相同的：

在VerificationController：

override func prepare(for segue: UIStoryboardSegue, sender: Any?) { 
    if segue.identifier == "segue" { 
     let secondVC = segue.destination as! SecondViewController 
     secondVC.verificationText = verification.text 
    } 
} 

然后在SecondViewController：

var verificationText:String? 

override func viewDidLoad() { 
    super.viewDidLoad() 

    // Do any additional setup after loading the view. 

    if (verificationText == "123") 
    { 
     label.text = myString1 
    } 
    else if (verificationText == "234") 
    { 
     label.text = myString1 
    } 

} 

希望它能帮助！