Sort array of dates ascending and starting from today date

Question

I have an array of dates (same current year but different month and day)

I'm trying to sort the dates ascending and starting with the next date closest to today.

How to do this ?

EDIT :

I'm trying with an array containing these dates :

let a = DateComponents(calendar: Calendar.current, year: 2017, month: 6, day: 6).date
let b = DateComponents(calendar: Calendar.current, year: 2017, month: 11, day: 9).date
let c = DateComponents(calendar: Calendar.current, year: 2017, month: 12, day: 10).date
let d = DateComponents(calendar: Calendar.current, year: 2017, month: 1, day: 22).date

The date today is 2017-09-25.
The output should be in this order :

2017-11-09  //b
2017-12-10  //c
2017-01-22  //d
2017-06-06  //a

The question is answered below https://stackoverflow.com/questions/38168594/sort-objects-in-array-by-date — sdfbhg, Sep 25 '17 at 15:16

Vini App · Answer 1 · 2017-09-25T18:13:46.367

1

Please check :

let dateObjectsFiltered = dateObjects.filter ({ $0 > Date() })

let datesSorted = dateObjectsFiltered.sorted { return $0 < $1 }
print(datesSorted)

// DatesObj : [2017-11-08 08:00:00, 2017-10-08 08:15:00, 2017-09-08 08:15:00, 2017-10-02 08:30:00, 2017-10-02 06:30:00]
// output :   [2017-10-02 06:30:00, 2017-10-02 08:30:00, 2017-10-08 08:15:00, 2017-11-08 08:00:00]

edited Sep 25 '17 at 18:13

answered Sep 25 '17 at 17:32

Vini App

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if the date today is 2017-10-06, it will show the first element of array (2017-10-02) and it's wrong, thx but it don't work. – user3722523 Sep 25 '17 at 17:48
`($0 > Date()) ? true : false }` is the same as just` $0 > Date()` – Alexander Sep 25 '17 at 18:11
Thanks for the suggestion. Updated the answer. – Vini App Sep 25 '17 at 18:14

score 1 · Accepted Answer · answered Sep 25 '17 at 19:41

1

This should work:

let dates  = [a!,b!,c!,d!]
let sorted =  dates.map{ ( ($0 < Date() ? 1 : 0), $0) }.sorted(by:<).map{$1}

answered Sep 25 '17 at 19:41

Alain T.

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Wow it work pretty nice, it was tricky indeed, I will try to understand. Thx a lot ! – user3722523 Sep 25 '17 at 19:47

score 0 · Answer 3 · answered Sep 25 '17 at 15:31

0

I've done this before like this:

let dates: [Date] = [
  Date.distantFuture,
  Date.distantPast,
  Date().addingTimeInterval(60*60*24*1),
  Date().addingTimeInterval(60*60*24*2),
  Date().addingTimeInterval(60*60*24*3),
  Date().addingTimeInterval(-60*60*24*1),
  Date().addingTimeInterval(-60*60*24*2),
  Date().addingTimeInterval(-60*60*24*3)
]

let referenceDate = Date()
let sortedDates = dates.sorted { (left, right) -> Bool in
  return abs(left.timeIntervalSince(referenceDate)) < abs(right.timeIntervalSince(referenceDate))
}

answered Sep 25 '17 at 15:31

mm282

453
3
7

Remove the `abs` – Alexander Sep 25 '17 at 18:18
They were sorted for the original question correctly (time away from a reference date / now); not the current ask tho. Accepted answer provides what's needed :) – mm282 Sep 25 '17 at 19:52

score 0 · Answer 4 · answered Sep 25 '17 at 16:02

0

I believe something like the following will do the job:

dates.sorted(by: { $0.timeIntervalSinceNow < $1.timeIntervalSinceNow })

answered Sep 25 '17 at 16:02

sCha

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don't work because I have some positive and some negative timeinterval – user3722523 Sep 25 '17 at 17:46
@user3722523 So what? – Alexander Sep 25 '17 at 18:21

score 0 · Answer 5 · answered Sep 25 '17 at 18:19

import Foundation

print("Dates:")
let dates: [Date] = [
    Date.distantFuture,
    Date.distantPast,
    Date().addingTimeInterval(60*60*24*1),
    Date().addingTimeInterval(60*60*24*2),
    Date().addingTimeInterval(60*60*24*3),
    Date().addingTimeInterval(-60*60*24*1),
    Date().addingTimeInterval(-60*60*24*2),
    Date().addingTimeInterval(-60*60*24*3)
]

dates.forEach{ print($0) }


let referenceDate = Date()

let sortedDates = dates.sorted {
    $0.timeIntervalSinceNow < $1.timeIntervalSinceNow
}

print("\r\nSorted dates:")
sortedDates.forEach{ print($0) }

Sort array of dates ascending and starting from today date

5 Answers5