how to get 30 minutes time slots array in between

Question

for example:- startDate:- 20-08-2018 10:00 AM endDate:- 20-08-2018 02:30 PM

Output:- ["10:00 AM", "10:30 AM", "11:00 AM", "11:30 AM", "12:00PM", "12:30 PM", "01:00 PM", "01:30 PM", "02:00 PM", "02:30 PM"]

var fromTime:Date = getFromTime fromTime = fromTime.addingTimeInterval(-1800)

    guard let toTime:Date  = timeFormat.date(from:endTime) else {
        return nil
    }

    var dateByAddingThirtyMinute : Date!
    let timeinterval : TimeInterval = toTime.timeIntervalSince(fromTime)
    let numberOfIntervals : Double = timeinterval / 3600;

    var timeArrayAM = [String]()
    var timeArrayPM = [String]()

    for _ in stride(from: 0, to: Int(numberOfIntervals * 2), by: 1) {

        dateByAddingThirtyMinute = fromTime.addingTimeInterval(1800)
        fromTime = dateByAddingThirtyMinute

        if let dateString = dateByAddingThirtyMinute.format(with: "hh:mm a") as? String {

            // print("Time after 30 min = \(dateString)")

            if temp == 0 {

                let time = dateString
                guard let getStopTime = timeFormat.date(from: time) else {

                    return nil
                }

                var stopTime = getStopTime

                var date = Date()
                date = date.addingTimeInterval(TimeInterval(advanceTimeInterval*60))
                let calendar = Calendar.current

                let year = calendar.component(.year, from: date)
                let month = calendar.component(.month, from: date)
                let day = calendar.component(.day, from: date)
                let hour = calendar.component(.hour, from: stopTime)
                let minute = calendar.component(.minute, from: stopTime)

                stopTime = calendar.date(bySetting: .year, value: year, of: stopTime)!
                stopTime = calendar.date(bySetting: .month, value: month, of: stopTime)!
                stopTime = calendar.date(bySetting: .day, value: day, of: stopTime)!
                stopTime = calendar.date(bySetting: .hour, value: hour, of: stopTime)!
                stopTime = calendar.date(bySetting: .minute, value: minute, of: stopTime)!

                let timeDifference = calendar.dateComponents([.hour, .minute], from: stopTime, to: date)

                // print_debug("************************************")
                // print(timeDifference.hour, timeDifference.minute)
                if timeDifference.hour! < 0 || timeDifference.minute! < 0 || (timeDifference.hour! == 0 && timeDifference.minute! == 0 ) {
                    showFirstTime = dateString
                    temp = 1
                }
                // print_debug("************************************")
            }

Answer 1

You can do this,

var array: [String] = []

let formatter = DateFormatter()
formatter.dateFormat = "dd-MM-yyyy hh:mm a"

let formatter2 = DateFormatter()
formatter2.dateFormat = "hh:mm a"

let startDate = "20-08-2018 10:00 AM"
let endDate = "20-08-2018 02:30 PM"

let date1 = formatter.date(from: startDate)
let date2 = formatter.date(from: endDate)

var i = 1
while true {
    let date = date1?.addingTimeInterval(TimeInterval(i*30*60))
    let string = formatter2.string(from: date!)

    if date! >= date2! {
        break;
    }

    i += 1
    array.append(string)
}
print(array)

Output of above is,

["10:30 AM", "11:00 AM", "11:30 AM", "12:00 PM", "12:30 PM", "01:00 PM", "01:30 PM", "02:00 PM", "02:30 PM"]