How do I add 1 day to an NSDate?

Question

Basically, as the title says. I'm wondering how I could add 1 day to an NSDate.

So if it were:

21st February 2011

It would become:

22nd February 2011

Or if it were:

31st December 2011

It would become:

1st January 2012.

Answer 1

Here is a general purpose method which lets you add/subtract any type of unit(Year/Month/Day/Hour/Second etc) in the specified date.

Using Swift 2.2

func addUnitToDate(unitType: NSCalendarUnit, number: Int, date:NSDate) -> NSDate {

    return NSCalendar.currentCalendar().dateByAddingUnit(
        unitType,
        value: number,
        toDate: date,
        options: NSCalendarOptions(rawValue: 0))!

}

print( addUnitToDate(.Day, number: 1, date: NSDate()) ) // Adds 1 Day To Current Date
print( addUnitToDate(.Hour, number: 1, date: NSDate()) ) // Adds 1 Hour To Current Date
print( addUnitToDate(.Minute, number: 1, date: NSDate()) ) // Adds 1 Minute To Current Date

// NOTE: You can use negative values to get backward values too

Answer 2

NSDateComponents *dayComponent = [[[NSDateComponents alloc] init] autorelease];
dayComponent.day = 1;

NSCalendar *theCalendar = [NSCalendar currentCalendar];
dateToBeIncremented = [theCalendar dateByAddingComponents:dayComponent toDate:dateToBeIncremented options:0];

Ok - I thought this was going to work for me. However, if you use it to add a day to the 31st March 2013, it'll return a date that has only 23 hours added to it. It may well actually have the 24, but using in calculations has only 23:00 hours added.

Similarly, if you blast forward to 28th Oct 2013, the code adds 25 hours resulting in a date time of 2013-10-28 01:00:00.

Very strange.

In order to add a day I was doing the thing at the top, adding the:

NSDate *newDate1 = [now dateByAddingTimeInterval:60*60*24*daysToAdd];

But this was a real mess for certain dates, principally due to daylight saving.

Objective-C, dates are a nightmare.

Answer 3

Since iOS 8 you can use NSCalendar.dateByAddingUnit

Example in Swift 1.x:

let today = NSDate()
let tomorrow = NSCalendar.currentCalendar()
    .dateByAddingUnit(
         .CalendarUnitDay, 
         value: 1, 
         toDate: today, 
         options: NSCalendarOptions(0)
    )

Swift 2.0:

let today = NSDate()
let tomorrow = NSCalendar.currentCalendar()
    .dateByAddingUnit(
        .Day, 
        value: 1, 
        toDate: today, 
        options: []
    )

Swift 3.0:

let today = Date()
let tomorrow = Calendar.current.date(byAdding: .day, value: 1, to: today)

Answer 4

Swift 3.0 very simple implemetation would be:

func dateByAddingDays(inDays:NSInteger)->Date{
    let today = Date()
    return Calendar.current.date(byAdding: .day, value: inDays, to: today)!
}

Answer 5

In swift you can make extension to add method in NSDate

extension NSDate {
    func addNoOfDays(noOfDays:Int) -> NSDate! {
        let cal:NSCalendar = NSCalendar.currentCalendar()
        cal.timeZone = NSTimeZone(abbreviation: "UTC")!
        let comps:NSDateComponents = NSDateComponents()
        comps.day = noOfDays
        return cal.dateByAddingComponents(comps, toDate: self, options: nil)
    }
}

you can use this as

NSDate().addNoOfDays(3)

Answer 6

Try this

 NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
 // now build a NSDate object for the next day
 NSDateComponents *offsetComponents = [[NSDateComponents alloc] init];
 [offsetComponents setDay:1];
 NSDate *nextDate = [gregorian dateByAddingComponents:offsetComponents toDate: [NSDate date] options:0];
 [offsetComponents release];
 [gregorian release];