Swift – Converting JSON date to Swift compatible date

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I am trying to convert a date in which the javascript code is generating the current date using the Date() function. But when I print it out, I am getting nil.

my code:

        let date2 = data?[0] as! String
        println(date2)

        var str = "2013-07-21T19:32:00Z"

        var dateFor: NSDateFormatter = NSDateFormatter()
        dateFor.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"

        var Date: NSDate? = dateFor.dateFromString(date2)

        println(Date)

date2 => is printing out 2015-05-15T21:58:00.066Z
Date => is printing nil
str is just for testing and works perfectly.

Anyone see any flaws in the code?

7 thoughts on “Swift – Converting JSON date to Swift compatible date”

  1. Swift 4+

    let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
let str = "2013-07-21T19:32:00Z"

if let date = dateFormatter.date(from: str) {
    print(date)
}

    Output: 2013-07-21 19:32:00 +0000

    Reply

  2. Use ISO8601DateFormatter per documentation going forward

    In macOS 10.12 and later or iOS 10 and later, use the
    ISO8601DateFormatter class when working with ISO 8601 date
    representations.

    import Foundation

let isoStr = "2020-02-18T11:40:01.000Z"

let isoDateFormatter = ISO8601DateFormatter()
isoDateFormatter.timeZone = TimeZone(secondsFromGMT: 0)
isoDateFormatter.formatOptions = [
    .withFullDate,
    .withFullTime,
    .withDashSeparatorInDate,
    .withFractionalSeconds]

if let isoDateFormatted = isoDateFormatter.date(from: isoStr) {
    print(isoDateFormatted)
}
    Reply

  3. The issue is that str and date2 two are not the same date format. str format is "yyyy-MM-dd'T'HH:mm:ssZ" while date2 format is "yyyy-MM-dd'T'HH:mm:ss.SSSZ". Besides that you should always set your dateFormatter’s locale to "en_US_POSIX" when parsing fixed-format dates:

    let date2 = "2015-05-15T21:58:00.066Z"

let dateFormatter = DateFormatter()
dateFormatter.locale = .init(identifier: "en_US_POSIX")
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZ"
if let date = dateFormatter.date(from: date2) {
    print(date)  // "2015-05-15 21:58:00 +0000"
}
    Reply

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