Question

您好我想在标签中显示用户的分数。我告诉它只要对象为零就要做什么，但由于某种原因，当标签加载时它仍然有错误。我该如何解决这个问题？

这是我的代码：

    let score: AnyObject? = PFUser.currentUser()!.objectForKey("score")

        self.SpotScore.text = ("Spot Score: " + (score! as! String))
        if score == nil{

            self.SpotScore.text = ("Spot Score: Create or Go to a Spot!")
        }

由于

Answer 1

使用可选绑定检查nil：

if let score = PFUser.currentUser()?["score"] as? String {
    self.SpotScore.text = "Spot Score: \(score)"
} else {
    self.SpotScore.text = "Spot Score: Create or Go to a Spot!"
}

或者您可以使用 nil-coalescing operator ??来创建score字符串：

let score = (PFUser.currentUser()?["score"] as? String) ?? "Create or Go to a Spot!"
self.SpotScore.text = "Spot Score: " + score

致命错误：当我的PFUser对象被打开时

1 个答案: