swift - 离线模式 Firebase 存储

Question

我正在创建这个函数来设置我存储在 firebase 存储中的图像并且工作正常但是当模拟器离线时，它不会通过我默认的本地保存图像

func downloadImageFromFirebase(_ imageNameOnFireBase: String, _ defaultLocalImageName: String, _ imageToBeReplaced: UIImageView) {
    let storage = Storage.storage()
    let reference: StorageReference = storage.reference().child(imageNameOnFireBase)
    let defaultImage = UIImage(named: defaultLocalImageName)
    reference.downloadURL { url , error in
        if error != nil {
            imageToBeReplaced.image = defaultImage
        }else{
            if let url = url {
                do {
                    let data = try Data.init(contentsOf: url)
                    imageToBeReplaced.image = UIImage(data: data)!
                } catch {
                    print("Error fetching URL")
                    imageToBeReplaced.image = defaultImage
                }
            } else {
                imageToBeReplaced.image = defaultImage
            }
        }
    }
}

如果模拟器或设备处于离线模式，我如何使该功能获取本地图像？

标签： swiftfirebasefirebase-storage