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

Details

• Xcode 11.4 (11E146), Swift 5.2

Solution

import Foundation

extension Date {

    typealias Component = (value: Int, type: Calendar.Component)

    init?(bySubtracting components: Component..., calendar: Calendar = Calendar.current, from date: Date) {
        guard let date = date.subtract(components, calendar: calendar) else { return nil }
        self = date
    }

    func subtract(_ components: Component..., calendar: Calendar = Calendar.current) -> Date? {
        subtract(components, calendar: calendar)
    }

    func subtract(_ components: [Component], calendar: Calendar = Calendar.current) -> Date? {
        components.reduce(self) { (result, component) -> Date? in
            guard let date = result else { return nil }
            return calendar.date(byAdding: component.type, value: (-1)*component.value, to: date)
        }
    }

    static func beforeNow(difference component: Component..., calendar: Calendar = Calendar.current) -> Date? {
        Date().subtract(component, calendar: calendar)
    }

    static func beforeNow(difference component: [Component], calendar: Calendar = Calendar.current) -> Date? {
        Date().subtract(component, calendar: calendar)
    }
}

extension Date {
    static func - (date: Date, component: Date.Component) -> Date? { date.subtract(component, calendar: Calendar.current) }
    static func -= (date: inout Date, component: Date.Component) {
        guard let newDate = date.subtract(component, calendar: Calendar.current) else { return }
        date = newDate
    }
}

Usage

var currentDate = Date()
let date1 = Date(bySubtracting: (30, .day), from: currentDate)

let date2 = Date().subtract((30, .day))

let date3 = Date().subtract([(1, .minute), (2, .hour), (3, .day), (4, .month)])

let component = Date.Component(value: 1, type: .day)
let date4 = Date.beforeNow(difference: component)

let date5 = Date.beforeNow(difference: (1, .minute), (2, .hour), (3, .day), (4, .month))

let date6 = Date.beforeNow(difference: [(1, .minute), (2, .hour), (3, .day), (4, .month)])

let date7 = currentDate - (1, .day)

currentDate -= Date.Component(value: 1, type: .day)

More

• Get components (hours, months, days...) from date
• Compare days by components
• Convert date to formated string date

Answer 2

According to your needs, you may choose one of the 3 following Swift 5 methods to get one hour ago from a Date instance.

---

1. date(byAdding:value:to:wrappingComponents:)

Calendar has a method called date(byAdding:value:to:wrappingComponents:). date(byAdding:value:to:wrappingComponents:) has the following declaration:

func date(byAdding component: Calendar.Component, value: Int, to date: Date, wrappingComponents: Bool = default) -> Date?

Returns a new Date representing the date calculated by adding an amount of a specific component to a given date.

The Playground code below shows how to use it:

import Foundation

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

print(now) // 2016-12-19 21:52:04 +0000
print(String(describing: oneHourAgo)) // Optional(2016-12-19 20:52:04 +0000)

---

2. date(byAdding:to:wrappingComponents:)

Calendar has a method called date(byAdding:to:wrappingComponents:). date(byAdding:value:to:wrappingComponents:) has the following declaration:

func date(byAdding components: DateComponents, to date: Date, wrappingComponents: Bool = default) -> Date?

Returns a new Date representing the date calculated by adding components to a given date.

The Playground code below shows how to use it:

import Foundation

let now = Date()

var components = DateComponents()
components.hour = -1
let oneHourAgo = Calendar.current.date(byAdding: components, to: now)

print(now) // 2016-12-19 21:52:04 +0000
print(String(describing: oneHourAgo)) // Optional(2016-12-19 20:52:04 +0000)

Alternative:

import Foundation

// Get the date that was 1hr before now
let now = Date()

let components = DateComponents(hour: -1)
let oneHourAgo = Calendar.current.date(byAdding: components, to: now)

print(now) // 2016-12-19 21:52:04 +0000
print(String(describing: oneHourAgo)) // Optional(2016-12-19 20:52:04 +0000)

---

3. addingTimeInterval(_:) (use with caution)

Date has a method called addingTimeInterval(_:). addingTimeInterval(_:) has the following declaration:

func addingTimeInterval(_ timeInterval: TimeInterval) -> Date

Return a new Date by adding a TimeInterval to this Date.

Note that this method comes with a warning:

This only adjusts an absolute value. If you wish to add calendrical concepts like hours, days, months then you must use a Calendar. That will take into account complexities like daylight saving time, months with different numbers of days, and more.

The Playground code below shows how to use it:

import Foundation

let now = Date()
let oneHourAgo = now.addingTimeInterval(-3600)

print(now) // 2016-12-19 21:52:04 +0000
print(oneHourAgo) // 2016-12-19 20:52:04 +0000

Answer 3

If you are using NSDate you can do:

let date = NSDate()
date.dateByAddingTimeInterval(-3600)

It will change the date object to be "1 hour ago".

Answer 4

let now = Date()
let nowMinusTwoAndAHalfHours = now - 2.5*60*60

print(now)
print(nowMinusTwoAndAHalfHours)

Answer 5

Use this method and paste in your helper class.

Updated for Swift 3 and Xcode 8.3

class func timeAgoSinceDate(_ date:Date,currentDate:Date, numericDates:Bool) -> String {
    let calendar = Calendar.current
    let now = currentDate
    let earliest = (now as NSDate).earlierDate(date)
    let latest = (earliest == now) ? date : 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())
    
    if (components.year! >= 2) {
        return "\(components.year!) years ago"
    } else if (components.year! >= 1){
        if (numericDates){
            return "1 year ago"
        } else {
            return "Last year"
        }
    } else if (components.month! >= 2) {
        return "\(components.month!) months ago"
    } else if (components.month! >= 1){
        if (numericDates){
            return "1 month ago"
        } else {
            return "Last month"
        }
    } else if (components.weekOfYear! >= 2) {
        return "\(components.weekOfYear!) weeks ago"
    } else if (components.weekOfYear! >= 1){
        if (numericDates){
            return "1 week ago"
        } else {
            return "Last week"
        }
    } else if (components.day! >= 2) {
        return "\(components.day!) days ago"
    } else if (components.day! >= 1){
        if (numericDates){
            return "1 day ago"
        } else {
            return "Yesterday"
        }
    } else if (components.hour! >= 2) {
        return "\(components.hour!) hours ago"
    } else if (components.hour! >= 1){
        if (numericDates){
            return "1 hour ago"
        } else {
            return "An hour ago"
        }
    } else if (components.minute! >= 2) {
        return "\(components.minute!) minutes ago"
    } else if (components.minute! >= 1){
        if (numericDates){
            return "1 minute ago"
        } else {
            return "A minute ago"
        }
    } else if (components.second! >= 3) {
        return "\(components.second!) seconds ago"
    } else {
        return "Just now"
    }
    
}

Use of this method:

var timeAgo:String=AppHelper.timeAgoSinceDate(date, numericDates: true)
Print("\(timeAgo)")   // Ex- 1 hour ago

Answer 6

In swift 5 You can use

      let earlyDate = Calendar.current.date( byAdding: .hour, value: -1, to: Date())
      let df = DateFormatter()
      df.dateFormat = "yyyy-MM-dd HH:mm:ss"
      let dateString = df.string(from: earlyDate!)

Out put will Be like bellow

Current DateTime--> 2019-12-20 09:40:08
One Hour Previous Date Time--> 2019-12-20 08:40:08