UIApplicationOpenURLOptionsKey.sourceApplication可以为零吗？

Question

最近在新的应用更新后，我们开始崩溃

let sourceApplication = options[UIApplicationOpenURLOptionsKey.sourceApplication] as! String

在以下代码中。我只是想知道为什么它可以是零或因为as而崩溃！字符串？

    func application(_ app: UIApplication, open url: URL, options: [UIApplicationOpenURLOptionsKey: Any] = [:]) -> Bool {
    CoreAnalytics.shared.record("AppDelegate", action: "Open URL")
    Branch.getInstance().handleDeepLink(url)
    let sourceApplication = options[UIApplicationOpenURLOptionsKey.sourceApplication] as! String
    let annotation = options[UIApplicationOpenURLOptionsKey.annotation]

    CleverTap.sharedInstance()?.handleOpen(url, sourceApplication: sourceApplication)

    return
        GIDSignIn.sharedInstance().handle(url, sourceApplication: sourceApplication, annotation: annotation) ||
        FBSDKApplicationDelegate.sharedInstance().application(app, open: url, sourceApplication: sourceApplication, annotation: annotation)
}

Answer 1

这是从Apple钱包通行证打开应用程序时发生的。