How can I get the date of previous month matching specified day ? in Swift

if I have this function getPreviousMonthDate(matchingDay day: Int) -> Date

Examples: following (dd/mm/yyyy)

• If Today is 25/07/2022 and I call getPreviousMonthDate(matchingDay: 27) : return value would be 27/06/2022 .

• If Today is 18/04/2022 and I call getPreviousMonthDate(matchingDay: 14) : return value would be 14/03/2022 .

• If Today is 15/01/2022 and I call getPreviousMonthDate(matchingDay: 16) : return value would be 16/12/2021 .

and so on...

CodePudding user response：

You can use date components as following:

func getPreviousMonthDate(matchingDay day: Int) -> Date {
    let calendar = Calendar.current
    let comps = calendar.dateComponents([.year, .month, .day], from: Date())
    var comps2 = DateComponents()
    comps2.year = comps.year
    comps2.month = comps.month! - 1
    comps2.day = day
    return calendar.date(from: comps2)!
}

I force-unwrapped the date to match your function declaration, I suggest that you deal with the optional dates properly though.