nextDate 如何考虑时区？

Question

有以下代码：

let start = DateComponents(calendar: .current, year: 2022, month: 4, day: 25).date!
let end = DateComponents(calendar: .current, year: 2022, month: 7, day: 2).date!
let dateInterval: DateInterval = .init(start: start, end: end)

let m2030 = dateInterval.dates(matching: .init(calendar: .current, timeZone: TimeZone(identifier: "Europe/Budapest"), hour: 20, minute: 30, weekday: 2))

extension DateInterval {
    func dates(matching components: DateComponents) -> [Date] {
        var start = self.start
        var dates: [Date] = []
        while let date = Calendar.current.nextDate(after: start, matching: components, matchingPolicy: .strict), date <= end {
            dates.append(date)
            start = date
        }
        return dates
    }
}

我在控制台中看到了这一点：

(lldb) po m2030
▿ 10 elements
  ▿ 0 : 2022-04-25 13:30:00 +0000
    - timeIntervalSinceReferenceDate : 672586200.0

为什么控制台说：13:30:00 +0000在布达佩斯中是15:30，尽管我的请求是显示的时间布达佩斯时间20:30？

我现在在国外，没关系吗？在柬埔寨。 :) +5小时到达布达佩斯。

Answer 1

您需要的是使用布达佩斯时区使用自定义日历。尝试这样：

---

extension DateInterval {
    func dates(matching components: DateComponents, using calendar: Calendar = .current) -> [Date] {
        var start = self.start
        var dates: [Date] = []
        while let date = calendar.nextDate(after: start, matching: components, matchingPolicy: .strict), date <= end {
            dates.append(date)
            start = date
        }
        return dates
    }
}

---

var budapestCalendar = Calendar(identifier: .iso8601)
budapestCalendar.timeZone = TimeZone(identifier: "Europe/Budapest")!

let start = DateComponents(calendar: budapestCalendar, year: 2022, month: 4, day: 25).date!
let end = DateComponents(calendar: budapestCalendar, year: 2022, month: 7, day: 2).date!
let dateInterval: DateInterval = .init(start: start, end: end)

let m2030 = dateInterval.dates(matching: .init(hour: 20, minute: 30, weekday: 2), using: budapestCalendar)

for date in m2030 {
    print(date)
}

这将打印：

2022-04-25 18:30:00 +0000
2022-05-02 18:30:00 +0000
2022-05-09 18:30:00 +0000
2022-05-16 18:30:00 +0000
2022-05-23 18:30:00 +0000
2022-05-30 18:30:00 +0000
2022-06-06 18:30:00 +0000
2022-06-13 18:30:00 +0000
2022-06-20 18:30:00 +0000
2022-06-27 18:30:00 +0000