Date 如何在Swift中解析/创建使用UTC时区分数秒(ISO 8601,RFC 3339)格式化的日期时间戳?
如何使用和的格式标准生成日期时间戳 目标是一个如下所示的字符串:Date 如何在Swift中解析/创建使用UTC时区分数秒(ISO 8601,RFC 3339)格式化的日期时间戳?,date,swift,time,iso8601,rfc3339,Date,Swift,Time,Iso8601,Rfc3339,如何使用和的格式标准生成日期时间戳 目标是一个如下所示的字符串: "2015-01-01T00:00:00.000Z" 格式: 年、月、日,作为“XXXX-XX-XX” 作为分隔符的字母“T” 小时、分钟、秒、毫秒,表示为“XX:XX:XX.XXX” 字母“Z”作为零偏移的区域指示器,又称UTC、GMT、祖鲁时间 最佳案例: Swift源代码,简单、简短、直观 不需要使用任何额外的框架、子项目、cocoapod、C代码等 我搜索过StackOverflow、谷歌、苹果等,但没有找到快速
"2015-01-01T00:00:00.000Z"
格式:
- 年、月、日,作为“XXXX-XX-XX”
- 作为分隔符的字母“T”
- 小时、分钟、秒、毫秒,表示为“XX:XX:XX.XXX”
- 字母“Z”作为零偏移的区域指示器,又称UTC、GMT、祖鲁时间
- Swift源代码,简单、简短、直观
- 不需要使用任何额外的框架、子项目、cocoapod、C代码等
var now = NSDate()
var formatter = NSDateFormatter()
formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"
formatter.timeZone = NSTimeZone(forSecondsFromGMT: 0)
println(formatter.stringFromDate(now))
请记住将区域设置设置为
en_US_POSIX
,如中所述。在Swift 3中:
let date = Date()
let formatter = DateFormatter()
formatter.locale = Locale(identifier: "en_US_POSIX")
formatter.timeZone = TimeZone(secondsFromGMT: 0)
formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZZZZZ"
print(formatter.string(from: date))
问题是,如果您使用的设备使用的是非公历,则年份将不符合RFC3339/ISO8601,除非您指定区域设置
以及时区
和日期格式
字符串
或者您可以使用ISO8601DateFormatter
来摆脱设置locale
和timeZone
的麻烦:
let date = Date()
let formatter = ISO8601DateFormatter()
formatter.formatOptions.insert(.withFractionalSeconds) // this is only available effective iOS 11 and macOS 10.13
print(formatter.string(from: date))
有关Swift 2格式副本,请参阅。Swift 4•iOS 11.2.1或更高版本
extension ISO8601DateFormatter {
convenience init(_ formatOptions: Options) {
self.init()
self.formatOptions = formatOptions
}
}
extension Formatter {
static let iso8601withFractionalSeconds: DateFormatter = {
let formatter = DateFormatter()
formatter.calendar = Calendar(identifier: .iso8601)
formatter.locale = Locale(identifier: "en_US_POSIX")
formatter.timeZone = TimeZone(secondsFromGMT: 0)
formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSXXXXX"
return formatter
}()
}
用法:
Date().description(with: .current) // Tuesday, February 5, 2019 at 10:35:01 PM Brasilia Summer Time"
let dateString = Date().iso8601withFractionalSeconds // "2019-02-06T00:35:01.746Z"
if let date = dateString.iso8601withFractionalSeconds {
date.description(with: .current) // "Tuesday, February 5, 2019 at 10:35:01 PM Brasilia Summer Time"
print(date.iso8601withFractionalSeconds) // "2019-02-06T00:35:01.746Z\n"
}
iOS 9•Swift 3或更高版本
extension ISO8601DateFormatter {
convenience init(_ formatOptions: Options) {
self.init()
self.formatOptions = formatOptions
}
}
extension Formatter {
static let iso8601withFractionalSeconds: DateFormatter = {
let formatter = DateFormatter()
formatter.calendar = Calendar(identifier: .iso8601)
formatter.locale = Locale(identifier: "en_US_POSIX")
formatter.timeZone = TimeZone(secondsFromGMT: 0)
formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSXXXXX"
return formatter
}()
}
可编码协议 如果在使用Codable时需要对该格式进行编码和解码 协议您可以创建自己的自定义日期编码/解码策略: 以及编码策略
extension JSONEncoder.DateEncodingStrategy {
static let iso8601withFractionalSeconds = custom {
var container = $1.singleValueContainer()
try container.encode(Formatter.iso8601withFractionalSeconds.string(from: $0))
}
}
操场测试
let dates = [Date()] // ["Feb 8, 2019 at 9:48 PM"]
编码
let encoder = JSONEncoder()
encoder.dateEncodingStrategy = .iso8601withFractionalSeconds
let data = try! encoder.encode(dates)
print(String(data: data, encoding: .utf8)!)
解码
let decoder = JSONDecoder()
decoder.dateDecodingStrategy = .iso8601withFractionalSeconds
let decodedDates = try! decoder.decode([Date].self, from: data) // ["Feb 8, 2019 at 9:48 PM"]
在我的例子中,我必须将DynamoDB-lastUpdated列(Unix时间戳)转换为正常时间 上次更新的初始值为:1460650607601-通过以下方式转换为2016-04-14 16:16:47+0000:
if let lastUpdated : String = userObject.lastUpdated {
let epocTime = NSTimeInterval(lastUpdated)! / 1000 // convert it from milliseconds dividing it by 1000
let unixTimestamp = NSDate(timeIntervalSince1970: epocTime) //convert unix timestamp to Date
let dateFormatter = NSDateFormatter()
dateFormatter.timeZone = NSTimeZone()
dateFormatter.locale = NSLocale.currentLocale() // NSLocale(localeIdentifier: "en_US_POSIX")
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
dateFormatter.dateFromString(String(unixTimestamp))
let updatedTimeStamp = unixTimestamp
print(updatedTimeStamp)
}
为了补充Leo Dabus的版本,我添加了对Swift和Objective-C编写的项目的支持,还添加了对可选毫秒的支持,这可能不是最好的,但您会明白这一点: Xcode 8和Swift 3
extension Date {
struct Formatter {
static let iso8601: DateFormatter = {
let formatter = DateFormatter()
formatter.calendar = Calendar(identifier: .iso8601)
formatter.locale = Locale(identifier: "en_US_POSIX")
formatter.timeZone = TimeZone(secondsFromGMT: 0)
formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSXXXXX"
return formatter
}()
}
var iso8601: String {
return Formatter.iso8601.string(from: self)
}
}
extension String {
var dateFromISO8601: Date? {
var data = self
if self.range(of: ".") == nil {
// Case where the string doesn't contain the optional milliseconds
data = data.replacingOccurrences(of: "Z", with: ".000000Z")
}
return Date.Formatter.iso8601.date(from: data)
}
}
extension NSString {
var dateFromISO8601: Date? {
return (self as String).dateFromISO8601
}
}
将来可能需要更改格式,这可能会导致应用程序中到处都有date.dateFromISO8601调用的小头痛。使用类和协议包装实现,在一个地方更改日期-时间格式调用会更简单。如果可能,使用RFC3339,这是一个更完整的表示。DateFormatProtocol和DateFormat非常适合依赖项注入
class AppDelegate: UIResponder, UIApplicationDelegate {
internal static let rfc3339DateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
internal static let localeEnUsPosix = "en_US_POSIX"
}
import Foundation
protocol DateFormatProtocol {
func format(date: NSDate) -> String
func parse(date: String) -> NSDate?
}
import Foundation
class DateFormat: DateFormatProtocol {
func format(date: NSDate) -> String {
return date.rfc3339
}
func parse(date: String) -> NSDate? {
return date.rfc3339
}
}
extension NSDate {
struct Formatter {
static let rfc3339: NSDateFormatter = {
let formatter = NSDateFormatter()
formatter.calendar = NSCalendar(calendarIdentifier: NSCalendarIdentifierISO8601)
formatter.locale = NSLocale(localeIdentifier: AppDelegate.localeEnUsPosix)
formatter.timeZone = NSTimeZone(forSecondsFromGMT: 0)
formatter.dateFormat = rfc3339DateFormat
return formatter
}()
}
var rfc3339: String { return Formatter.rfc3339.stringFromDate(self) }
}
extension String {
var rfc3339: NSDate? {
return NSDate.Formatter.rfc3339.dateFromString(self)
}
}
class DependencyService: DependencyServiceProtocol {
private var dateFormat: DateFormatProtocol?
func setDateFormat(dateFormat: DateFormatProtocol) {
self.dateFormat = dateFormat
}
func getDateFormat() -> DateFormatProtocol {
if let dateFormatObject = dateFormat {
return dateFormatObject
} else {
let dateFormatObject = DateFormat()
dateFormat = dateFormatObject
return dateFormatObject
}
}
}
如果您想将
ISO8601DateFormatter()
与来自Rails 4+JSON提要的日期一起使用(当然不需要millis),则需要在格式化程序上设置一些选项,使其正常工作,否则date(from:string)
函数将返回nil。以下是我正在使用的:
extension Date {
init(dateString:String) {
self = Date.iso8601Formatter.date(from: dateString)!
}
static let iso8601Formatter: ISO8601DateFormatter = {
let formatter = ISO8601DateFormatter()
formatter.formatOptions = [.withFullDate,
.withTime,
.withDashSeparatorInDate,
.withColonSeparatorInTime]
return formatter
}()
}
以下是在操场屏幕截图中使用选项的结果:
为了进一步赞扬安德烈·托雷斯·马洛金和利奥·达布斯,我有一个保留分数秒的版本。我在任何地方都找不到它的文档,但苹果在输入和输出上都将分数秒截断为微秒(精度为3位数)(即使使用SSS指定,与之相反) 我应该强调,对于大多数用例来说,这可能不是必需的。在线日期通常不需要毫秒精度,当需要毫秒精度时,最好使用不同的数据格式。但有时必须以特定的方式与预先存在的系统进行互操作 Xcode 8/9和Swift 3.0-3.2
extension Date {
struct Formatter {
static let iso8601: DateFormatter = {
let formatter = DateFormatter()
formatter.calendar = Calendar(identifier: .iso8601)
formatter.locale = Locale(identifier: "en_US_POSIX")
formatter.timeZone = TimeZone(identifier: "UTC")
formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSSSSXXXXX"
return formatter
}()
}
var iso8601: String {
// create base Date format
var formatted = DateFormatter.iso8601.string(from: self)
// Apple returns millisecond precision. find the range of the decimal portion
if let fractionStart = formatted.range(of: "."),
let fractionEnd = formatted.index(fractionStart.lowerBound, offsetBy: 7, limitedBy: formatted.endIndex) {
let fractionRange = fractionStart.lowerBound..<fractionEnd
// replace the decimal range with our own 6 digit fraction output
let microseconds = self.timeIntervalSince1970 - floor(self.timeIntervalSince1970)
var microsecondsStr = String(format: "%.06f", microseconds)
microsecondsStr.remove(at: microsecondsStr.startIndex)
formatted.replaceSubrange(fractionRange, with: microsecondsStr)
}
return formatted
}
}
extension String {
var dateFromISO8601: Date? {
guard let parsedDate = Date.Formatter.iso8601.date(from: self) else {
return nil
}
var preliminaryDate = Date(timeIntervalSinceReferenceDate: floor(parsedDate.timeIntervalSinceReferenceDate))
if let fractionStart = self.range(of: "."),
let fractionEnd = self.index(fractionStart.lowerBound, offsetBy: 7, limitedBy: self.endIndex) {
let fractionRange = fractionStart.lowerBound..<fractionEnd
let fractionStr = self.substring(with: fractionRange)
if var fraction = Double(fractionStr) {
fraction = Double(floor(1000000*fraction)/1000000)
preliminaryDate.addTimeInterval(fraction)
}
}
return preliminaryDate
}
}
延期日期{
结构格式化程序{
静态let iso8601:DateFormatter={
let formatter=DateFormatter()
formatter.calendar=日历(标识符:.iso8601)
formatter.locale=locale(标识符:“en_US_POSIX”)
formatter.timeZone=时区(标识符:“UTC”)
formatter.dateFormat=“yyyy-MM-dd'T'HH:MM:ss.ssss xxxxx”
返回格式化程序
}()
}
var iso8601:字符串{
//创建基准日期格式
var formatted=DateFormatter.iso8601.string(from:self)
//Apple返回毫秒精度。查找小数部分的范围
如果let fractionStart=格式化的.range(of:“.”),
让fractionEnd=formatted.index(fractionStart.lowerBound,offsetBy:7,limitedBy:formatted.endIndex){
让fractionRange=fractionStart.lowerBound..有一个新的ISO8601DateFormatter
类,让您仅用一行创建字符串。为了向后兼容,我使用了一个旧的C库。我希望这对其他人有用
Swift 3.0
extension Date {
var iso8601: String {
if #available(OSX 10.12, iOS 10.0, watchOS 3.0, tvOS 10.0, *) {
return ISO8601DateFormatter.string(from: self, timeZone: TimeZone.current, formatOptions: .withInternetDateTime)
} else {
var buffer = [CChar](repeating: 0, count: 25)
var time = time_t(self.timeIntervalSince1970)
strftime_l(&buffer, buffer.count, "%FT%T%z", localtime(&time), nil)
return String(cString: buffer)
}
}
}
在iOS10或更高版本上使用ISO8601DateFormatter
在iOS9或更早版本上使用DateFormatter
斯威夫特4
没有一些手动字符串掩码或时间格式化程序
import Foundation
struct DateISO: Codable {
var date: Date
}
extension Date{
var isoString: String {
let encoder = JSONEncoder()
encoder.dateEncodingStrategy = .iso8601
guard let data = try? encoder.encode(DateISO(date: self)),
let json = try? JSONSerialization.jsonObject(with: data, options: .allowFragments) as? [String: String]
else { return "" }
return json?.first?.value ?? ""
}
}
let dateString = Date().isoString
斯威夫特5
如果您的目标是iOS 11.0+/macOS 10.13+,只需将ISO8601DateFormatter
与withInternetDateTime
和withFractilSeconds
选项一起使用,如下所示:
let date = Date()
let iso8601DateFormatter = ISO8601DateFormatter()
iso8601DateFormatter.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
let string = iso8601DateFormatter.string(from: date)
// string looks like "2020-03-04T21:39:02.112Z"
基于对象范例中可接受的答案
class ISO8601Format
{
let format: ISO8601DateFormatter
init() {
let format = ISO8601DateFormatter()
format.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
format.timeZone = TimeZone(secondsFromGMT: 0)!
self.format = format
}
func date(from string: String) -> Date {
guard let date = format.date(from: string) else { fatalError() }
return date
}
func string(from date: Date) -> String { return format.string(from: date) }
}
class ISO8601Time
{
let date: Date
let format = ISO8601Format() //FIXME: Duplication
required init(date: Date) { self.date = date }
convenience init(string: String) {
let format = ISO8601Format() //FIXME: Duplication
let date = format.date(from: string)
self.init(date: date)
}
func concise() -> String { return format.string(from: date) }
func description() -> String { return date.description(with: .current) }
}
胼胝体
let now = Date()
let time1 = ISO8601Time(date: now)
print("time1.concise(): \(time1.concise())")
print("time1: \(time1.description())")
let time2 = ISO8601Time(string: "2020-03-24T23:16:17.661Z")
print("time2.concise(): \(time2.concise())")
print("time2: \(time2.description())")
添加相反的转换扩展名会很有用:扩展字符串{var dateFormattedISO8601:NSDate?{return NSDate.Date.formatterISO8601.dateFromString(self)}
请注意,这会降低一点精度,因此确保通过生成的字符串而不是时间间隔来比较日期的相等性非常重要。let now=NSDate()let stringFromDate=now.iso8601 let dateFromString=stringFromDate.datefromsiso8601!XCTAssertEqual(now.timeIntervalSince1970,dateFromString.timeIntervalSince1
let date = Date()
let iso8601DateFormatter = ISO8601DateFormatter()
iso8601DateFormatter.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
let string = iso8601DateFormatter.string(from: date)
// string looks like "2020-03-04T21:39:02.112Z"
class ISO8601Format
{
let format: ISO8601DateFormatter
init() {
let format = ISO8601DateFormatter()
format.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
format.timeZone = TimeZone(secondsFromGMT: 0)!
self.format = format
}
func date(from string: String) -> Date {
guard let date = format.date(from: string) else { fatalError() }
return date
}
func string(from date: Date) -> String { return format.string(from: date) }
}
class ISO8601Time
{
let date: Date
let format = ISO8601Format() //FIXME: Duplication
required init(date: Date) { self.date = date }
convenience init(string: String) {
let format = ISO8601Format() //FIXME: Duplication
let date = format.date(from: string)
self.init(date: date)
}
func concise() -> String { return format.string(from: date) }
func description() -> String { return date.description(with: .current) }
}
let now = Date()
let time1 = ISO8601Time(date: now)
print("time1.concise(): \(time1.concise())")
print("time1: \(time1.description())")
let time2 = ISO8601Time(string: "2020-03-24T23:16:17.661Z")
print("time2.concise(): \(time2.concise())")
print("time2: \(time2.description())")