问题描述
我有一个使用 Swift 4 编写的项目(iOS 部分)。我将其更新为 5,但现在我收到了此警告。我已经尝试按照建议修复它,但每次都会遇到不同的错误。你能帮我吗?
func saveData(data: BloodData) {
if let defaults = getUserDefaults() {
BloodData.registerClassName()
let encodedData: Data = NSKeyedArchiver.archivedData(withRootObject: data)
defaults.set(encodedData,forKey: dataKey)
defaults.synchronize()
}
}
警告
archivedData(withRootObject:)' was deprecated in iOS 12.0: Use +archivedDataWithRootObject:requiringSecureCoding:error: instead
func getData() -> BloodData? {
BloodData.registerClassName()
if let defaults = getUserDefaults(),let data = defaults.data(forKey: dataKey),let decodedData = NSKeyedUnarchiver.unarchiveObject(with: data) as? BloodData {
return computeData(data: decodedData)
}
return nil
}
警告
'unarchiveObject(with:)' was deprecated in iOS 12.0: Use +unarchivedobjectOfClass:fromData:error: instead
private func computeData(data: BloodData) -> BloodData? {
let today = Date()
let calendar = Calendar.current
let date1 = calendar.date(bySettingHour: 12,minute: 00,second: 00,of: calendar.startOfDay(for: data.readingDate))!
let date2 = calendar.date(bySettingHour: 12,of: calendar.startOfDay(for: today))!
let components = calendar.dateComponents([.day],from: date1,to: date2)
let dayDiff = components.day ?? 0
let newBloodData = BloodData(
whiteCells: data.whiteCells - dayDiff,fullBlood: data.fullBlood - dayDiff,platelet: data.platelet - dayDiff,redCells1: data.redCells1 - dayDiff,redCells2: data.redCells2 - dayDiff,bloodplasma: data.bloodplasma - dayDiff,readingDate: date2
)
return newBloodData
}
解决方法
在大多数情况下使用 Swift 编码时,错误不是很有帮助。 第一个是不言自明的,除了建议的方法可能会引发错误。您可以删除 throw 关键字并使用 try? 忽略错误?如果您愿意,但最好捕获并处理错误:
func save(blood: BloodData,forKey defaultName: String = "BloodDataKey") { // or forKey defaultName: String = dataKey
guard let data = try? NSKeyedArchiver.archivedData(withRootObject: blood,requiringSecureCoding: false) else { return }
UserDefaults.standard.set(data,forKey: defaultName)
}
第二个错误根本没有帮助。您可以使用 NSKeyedUnarchiver 的方法 unarchiveTopLevelObjectWithData 并且它也会抛出:
func getBlood(forKey defaultName: String = "BloodDataKey") -> BloodData? { // or forKey defaultName: String = dataKey
guard let data = UserDefaults.standard.data(forKey: defaultName) else { return nil }
guard let bloodData = (try? NSKeyedUnarchiver.unarchiveTopLevelObjectWithData(data)) as? BloodData else { return nil }
return computeData(data: bloodData)
}