您可以使用DateFormatter dateFormat "q"并将其转换为整数。
代码语言：javascript复制extension Formatter {
static let quarter: DateFormatter = {
let formatter = DateFormatter()
formatter.calendar = Calendar(identifier: .iso8601)
formatter.locale = Locale(identifier: "en_US_POSIX")
formatter.dateFormat = "q"
return formatter
}()
}代码语言：javascript复制extension Calendar {
static let iso8601 = Calendar(identifier: .iso8601)
}
extension Date {
var year: Int { return Calendar.iso8601.dateComponents([.year], from: self).year ?? 0 }
var quarter: Int { return Int(Formatter.quarter.string(from: self))! }
var firstDayOfYear: Date { return DateComponents(calendar: .iso8601, year: year, month: 1, day: 1).date!}
var firstDayOfNextYear: Date { return DateComponents(calendar: .iso8601, year: year.advanced(by: 1), month: 1, day: 1).date! }
var quarters: (q1: Int, q2: Int, q3: Int, q4: Int) {
var date = firstDayOfYear
var q1 = 0, q2 = 0, q3 = 0, q4 = 0
while date < firstDayOfNextYear {
switch date.quarter {
case 1: q1 += 1
case 2: q2 += 1
case 3: q3 += 1
case 4: q4 += 1
default:
break
}
date = Calendar.iso8601.date(byAdding: DateComponents(day: 1), to: date)!
}
return (q1: q1, q2: q2, q3: q3, q4: q4)
}
}操场测试：
代码语言：javascript复制Date().quarter // 2
Date().firstDayOfYear.quarter // 1
Date().quarters // q1 90, q2 91, q3 92, q4 92)