Date from String using DateFormatter returning nil

Question

I've a String like yyyy-MM-dd and I want create a Date with this.

static func dateFromStringWithBarra(date : String) -> String {
    print("DATE: \(date)")
    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = "yyyy-MM-dd"
    let date_from_format = dateFormatter.date(from: date)
    print("date_from_format: \(date_from_format)")
    dateFormatter.dateFormat = "dd/MM/yyyy"
    print("date_from_format: \(date_from_format)")
    return dateFormatter.string(from: date_from_format!) // <- nil
}

OUTPUT:

DATE: 2018-11-04 date_from_format: nil date_from_format: nil

Works fine for me on the Swift playgrounds. (Xcode 10, Swift 4.2) — Rakesha Shastri, Oct 08 '18 at 16:40
No, this is correct. But I solve using `dateFormatter.isLenient = true`. I don't know why, but is works. — Augusto, Oct 08 '18 at 16:48
if `isLenient` worked that means you have a problem with your date string. `isLenient = true` means something like guessing a possible true value from given string. Eg. 2018/02/29. there is no 29 Feb so when `isLenient = true` it will become March 1. with `isLenient = false` it will be nil — RJE, Oct 08 '18 at 17:20
@Augusto: What is your timezone? `print(TimeZone.current.identifier)` — Martin R, Oct 08 '18 at 18:01

score 0 · Answer 1 · answered Apr 30 '19 at 00:23

0

I had the same problem, mine was solved by some reason just by adding the locale to the DateFormatter:

let dateFormatter = DateFormatter()
dateFormatter.locale = Locale(identifier: "es_MX_POSIX")

Hope it helps.

answered Apr 30 '19 at 00:23

Samir Duran Kuri

16
1

score -1 · Answer 2 · answered Oct 08 '18 at 17:11

-1

A few things about that code:

1) Not sure why you use two different date formats 2) You should avoid if possible to use force unwrapping, in this case probably guard would be a good choice.

Meaning that the code should look more like this:

let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd"

guard let date_from_format = dateFormatter.date(from: date) else {
    return ""
}
return dateFormatter.string(from: date_from_format)

answered Oct 08 '18 at 17:11

Pablo

97
4

The point of two formats is to convert a date string to a new date string in a different format. Your code just returns the same string so there's no point to it. And your answer doesn't explain the issue. – rmaddy Oct 08 '18 at 17:20

Date from String using DateFormatter returning nil

2 Answers2