How to get 1 hour ago from a date in iOS swift?

Question

I have been researching, but I couldnt find exact solution for my problem. I have been trying to get 1 hour ago from a date. How can I achieve this in swift?

Answer 1

This works for iOS 13 / Swift 5. Credit goes to Sourabh Sharma

func timeAgoSinceNow(numericDates: Bool = true) -> String {
    let calendar = Calendar.current
    let now = Date()
    let earliest = (now as NSDate).earlierDate(self)
    let latest = (earliest == now) ? self : now
    let components: DateComponents = (calendar as NSCalendar).components([NSCalendar.Unit.minute,
                                                                          NSCalendar.Unit.hour,
                                                                          NSCalendar.Unit.day,
                                                                          NSCalendar.Unit.weekOfYear,
                                                                          NSCalendar.Unit.month,
                                                                          NSCalendar.Unit.year,
                                                                          NSCalendar.Unit.second],
                                                                         from: earliest,
                                                                         to: latest,
                                                                         options: NSCalendar.Options())

    guard
        let year = components.year,
        let month = components.month,
        let weekOfYear = components.weekOfYear,
        let day = components.day,
        let hour = components.hour,
        let minute = components.minute,
        let second = components.second
    else { return "A while ago"}

    if year >= 1 {
        return year >= 2 ? "\(year) years ago" : numericDates ? "1 year ago" : "Last year"
    } else if month >= 1 {
        return month >= 2 ? "\(month) months ago" : numericDates ? "1 month ago" : "Last month"
    } else if weekOfYear >= 1 {
        return weekOfYear >= 2 ? "\(weekOfYear) weeks ago" : numericDates ? "1 week ago" : "Last week"
    } else if day >= 1 {
        return day >= 2 ? "\(day) days ago" : numericDates ? "1 day ago" : "Yesterday"
    } else if hour >= 1 {
        return hour >= 2 ? "\(hour) hours ago" : numericDates ? "1 hour ago" : "An hour ago"
    } else if minute >= 1 {
        return minute >= 2 ? "\(minute) minutes ago" : numericDates ? "1 minute ago" : "A minute ago"
    } else {
        return second >= 3 ? "\(second) seconds ago" : "Just now"
    }
}

Usage:

var date = Date() // Or any date you wish to convert to text
print("\(date.timeAgoSinceNow())") // "Just Now"

Answer 2

Please read the NSDate class reference.

let oneHourAgo = NSDate.dateWithTimeIntervalSinceNow(-3600)

should do it.

Or, for any NSDate object:

let oneHourBack = myDate.dateByAddingTimeInterval(-3600)

Swift 4:

let oneHourAgo = NSDate(timeIntervalSinceNow: -3600)

Answer 3

I achieve time ago functionality by creating extension of Date. Which is given below:

extension Date {
 // Returns the number of years 
 func yearsCount(from date: Date) -> Int {
    return Calendar.current.dateComponents([.year], from: date, to: self).year ?? 0
 }
 // Returns the number of months
 func monthsCount(from date: Date) -> Int {
    return Calendar.current.dateComponents([.month], from: date, to: self).month ?? 0
 }
 // Returns the number of weeks
 func weeksCount(from date: Date) -> Int {
    return Calendar.current.dateComponents([.weekOfMonth], from: date, to: self).weekOfMonth ?? 0
 }
 // Returns the number of days
 func daysCount(from date: Date) -> Int {
    return Calendar.current.dateComponents([.day], from: date, to: self).day ?? 0
 }
 // Returns the number of hours
 func hoursCount(from date: Date) -> Int {
    return Calendar.current.dateComponents([.hour], from: date, to: self).hour ?? 0
 }
 // Returns the number of minutes
func minutesCount(from date: Date) -> Int {
    return Calendar.current.dateComponents([.minute], from: date, to: self).minute ?? 0
 }
 // Returns the number of seconds
 func secondsCount(from date: Date) -> Int {
    return Calendar.current.dateComponents([.second], from: date, to: self).second ?? 0
 }
 // Returns time ago by checking if the time differences between two dates are in year or months or weeks or days or hours or minutes or seconds
 func timeAgo(from date: Date) -> String {
    if yearsCount(from: date)   > 0 { return "\(yearsCount(from: date))years ago"   }
    if monthsCount(from: date)  > 0 { return "\(monthsCount(from: date))months ago"  }
    if weeksCount(from: date)   > 0 { return "\(weeksCount(from: date))weeks ago"   }
    if daysCount(from: date)    > 0 { return "\(daysCount(from: date))days ago"    }
    if hoursCount(from: date)   > 0 { return "\(hoursCount(from: date))hours ago"   }
    if minutesCount(from: date) > 0 { return "\(minutesCount(from: date))minutes ago" }
    if secondsCount(from: date) > 0 { return "\(secondsCount(from: date))seconds ago" }
    return ""
  }
}

Then i get the time ago by calculating the difference between current date and specified date:

   let timeAgo = Date().timeAgo(from: sender.date)

Answer 4

You can also use an operator

let date = Date()
let anHourAgo = date - TimeInterval(3600.0)

Apple Docs: https://developer.apple.com/documentation/foundation/date/2293436

Answer 5

For correct calculations involving NSDate that take into account all edge cases of different calendars (e.g. switching between day saving time) you should use NSCalendar class:

Swift 3+

let earlyDate = Calendar.current.date(
  byAdding: .hour, 
  value: -1, 
  to: Date())

Older

// Get the date that was 1hr before now
let earlyDate = NSCalendar.currentCalendar().dateByAddingUnit(
       .Hour,
       value: -1, 
       toDate: NSDate(),
       options: [])

Answer 6

for Swift 2:

extension NSDate {
    func after(value: Int, calendarUnit:NSCalendarUnit) -> NSDate {
        return calendar.dateByAddingUnit(calendarUnit, value: value, toDate: self, options: [])!
    }
}

how to use:

let lastHour = NSDate().after(-1, calendarUnit: .Hour)