ios - 在 Switch 语句失败后检查下一个案例的方法？

Question

在 Swift 中 fallthrough 之后，有什么方法可以检查下一个案例吗？这似乎是编写简洁代码的好方法。

    case 1...8:

        self.correctAnswerLabelOne.text = answerLabelOne?.firstObject as? String
        self.correctAnswerLabelOne.alpha = 0.0
        self.correctAnswerLabelOne.hidden = false
        self.fadeAnimation(self.correctAnswerLabelOne, duration: 0.3, delay: 0.0, alpha: 1.0, options: .CurveEaseIn)

        fallthrough

    case 2...8:

        self.correctAnswerLabelTwo.text = answerLabelTwo?.firstObject as? String
        self.correctAnswerLabelTwo.alpha = 0.0
        self.correctAnswerLabelTwo.hidden = false
        self.fadeAnimation(self.correctAnswerLabelTwo, duration: 0.3, delay: 0.0, alpha: 1.0, options: .CurveEaseIn)

        fallthrough

    case 3...8:

        self.correctAnswerLabelThree.text = answerLabelThree?.firstObject as? String
        self.correctAnswerLabelThree.alpha = 0.0
        self.correctAnswerLabelThree.hidden = false
        self.fadeAnimation(self.correctAnswerLabelThree, duration: 0.3, delay:     0.0, alpha: 1.0, options: .CurveEaseIn)

如果 case 是 3:不必将 case 1 和 case 2 中的代码添加到 case 3 我想激活第一种情况，第二种情况，然后是第三种情况。我可以在每个案例中使用 if 语句，但这似乎不是最好的方法。是否有另一种类型的控制流更适合此目的，还是只需要一直复制代码？

在我看来，在 switch 内部，continue 似乎是触发 Switch 继续其检查 case 语句业务的合乎逻辑的候选者。

更新:

将 if 语句 添加到预设 fallthrough 中即可完成工作。它仍然没有我预期的那么“优雅”，但它确实有效......

    switch(numberOfAnswers) {

    case 1...8:

        self.correctAnswerLabelOne.text = answerLabelOne?.firstObject as? String
        self.correctAnswerLabelOne.alpha = 0.0
        self.correctAnswerLabelOne.hidden = false
        self.fadeAnimation(self.correctAnswerLabelOne, duration: 0.3, delay: 0.0, alpha: 1.0, options: .CurveEaseIn)

        if numberOfAnswers > 1 {

            fallthrough

        }

    case 2...8:

        self.correctAnswerLabelTwo.text = answerLabelTwo?.firstObject as? String
        self.correctAnswerLabelTwo.alpha = 0.0
        self.correctAnswerLabelTwo.hidden = false

        self.fadeAnimation(self.correctAnswerLabelTwo, duration: 0.3, delay: 0.0, alpha: 1.0, options: .CurveEaseIn)

        if numberOfAnswers > 2 {

            fallthrough

        }

Answer 1

如果 switch 语句被反转，你的代码还能工作吗？例如

switch(numberOfAnswers) {

case 2...8:

    self.correctAnswerLabelTwo.text = answerLabelTwo?.firstObject as? String
    self.correctAnswerLabelTwo.alpha = 0.0
    self.correctAnswerLabelTwo.hidden = false

    self.fadeAnimation(self.correctAnswerLabelTwo, duration: 0.3, delay: 0.0, alpha: 1.0, options: .CurveEaseIn)

    if numberOfAnswers > 2 {

        fallthrough

    }

case 1...8:

    self.correctAnswerLabelOne.text = answerLabelOne?.firstObject as? String
    self.correctAnswerLabelOne.alpha = 0.0
    self.correctAnswerLabelOne.hidden = false
    self.fadeAnimation(self.correctAnswerLabelOne, duration: 0.3, delay: 0.0, alpha: 1.0, options: .CurveEaseIn)

    if numberOfAnswers > 1 {

        fallthrough

    }

那么对每个案例的评估并不重要，因为无论如何，上面案例的范围都包含在下面案例的范围内