ios - 为什么在失败的 if 语句之后不会出现警报？

Question

我试图在用户输入的密码与他们输入的密码确认不匹配时显示警告。然而，当它们不匹配时，segue 仍然会发生。谢谢

@IBAction func signUpAction(_ sender: Any) {
    if password.text != passwordConfirm.text {
        let alertController = UIAlertController(title: "Password Incorrect", message: "Please re-type password", preferredStyle: .alert)
        let defaultAction = UIAlertAction(title: "OK", style: .cancel, handler: nil)

        alertController.addAction(defaultAction)
        self.present(alertController, animated: true, completion: nil)
    }
    else{
        Auth.auth().createUser(withEmail: email.text!, password: password.text!){ (user, error) in
            if error == nil {
                self.performSegue(withIdentifier: "signupToHome", sender: self)
            }
            else{
                let alertController = UIAlertController(title: "Error", message: error?.localizedDescription, preferredStyle: .alert)
                let defaultAction = UIAlertAction(title: "OK", style: .cancel, handler: nil)

                alertController.addAction(defaultAction)
                self.present(alertController, animated: true, completion: nil)
            }
        }
    }

Answer 1

看来您将 segue 挂接到按钮上，将其删除并使其成为 vc 本身的来源(将其从 IB 中 vc 的黄色圆形图标顶部拖动)，因为将 segue 附加到按钮将运行它 Action 的内在逻辑