Question

How to create an array of dates between a start and end date in Swift

Answer 1

import Foundation

func generateDates(from start: Date, to end: Date) -> [Date] {
    var dates: [Date] = []
    let calendar = Calendar.current

    guard start <= end else { return dates }

    var current = start
    while current <= end {
        dates.append(current)
        current = calendar.date(byAdding: .day, value: 1, to: current)!
    }

    return dates
}

let calendar = Calendar.current
let start = calendar.date(from: DateComponents(year: 2026, month: 1, day: 3))!
let end   = calendar.date(from: DateComponents(year: 2026, month: 1, day: 12))!

let dates = generateDates(from: start, to: end)

print("Generated \(dates.count) dates:")
let formatter = DateFormatter()
formatter.dateFormat = "yyyy-MM-dd"

for d in dates {
    print(formatter.string(from: d))
}



/*
run:

Generated 10 dates:
2026-01-03
2026-01-04
2026-01-05
2026-01-06
2026-01-07
2026-01-08
2026-01-09
2026-01-10
2026-01-11
2026-01-12

*/

 

70+ SQL courses for beginners and professionals

Answer 2

import Foundation

func dateRange(from start: Date, to end: Date) -> [Date] {
    let calendar = Calendar.current

    return sequence(state: start) { current in
        guard current <= end else { return nil }
        defer { current = calendar.date(byAdding: .day, value: 1, to: current)! }
        return current
    }.map { $0 }
    // .map on a sequence returns an Array, because the return type of the function forces it.
}

let calendar = Calendar.current
let start = calendar.date(from: DateComponents(year: 2026, month: 1, day: 3))!
let end   = calendar.date(from: DateComponents(year: 2026, month: 1, day: 12))!

let formatter = DateFormatter()
formatter.dateFormat = "yyyy-MM-dd"

let dates = dateRange(from: start, to: end)

print("Generated \(dates.count) dates:")
dates.forEach { print(formatter.string(from: $0)) }



/*
run:

Generated 10 dates:
2026-01-03
2026-01-04
2026-01-05
2026-01-06
2026-01-07
2026-01-08
2026-01-09
2026-01-10
2026-01-11
2026-01-12

*/

 

70+ SQL courses for beginners and professionals