How do I convert a date/time string into a different date string?

Question

How will I convert this datetime from the date?

From this: 2016-02-29 12:24:26
to: Feb 29, 2016

So far, this is my code and it returns a nil value:

let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "MM-dd-yyyy"
dateFormatter.timeZone = NSTimeZone(name: "UTC")
let date: NSDate? = dateFormatter.dateFromString("2016-02-29 12:24:26")
print(date)

Any one looking for another date formats check [this](http://www.unicode.org/reports/tr35/tr35-dates.html#8-date-format-patterns) — udi, Sep 07 '22 at 05:31

score 585 · Answer 1 · edited Dec 01 '22 at 08:59

585

This may be useful for who want to use dateformatter.dateformat;

if you want 12.09.18 you use dateformatter.dateformat = "dd.MM.yy"

Wednesday, Sep 12, 2018           --> EEEE, MMM d, yyyy
09/12/2018                        --> MM/dd/yyyy
09-12-2018 14:11                  --> MM-dd-yyyy HH:mm
Sep 12, 2:11 PM                   --> MMM d, h:mm a
September 2018                    --> MMMM yyyy
Sep 12, 2018                      --> MMM d, yyyy
Wed, 12 Sep 2018 14:11:54 +0000   --> E, d MMM yyyy HH:mm:ss Z
2018-09-12T14:11:54+0000          --> yyyy-MM-dd'T'HH:mm:ssZ
12.09.18                          --> dd.MM.yy
10:41:02.112                      --> HH:mm:ss.SSS

Here are alternatives:

Era: G (AD), GGGG (Anno Domini)
Year: y (2018), yy (18), yyyy (2018)
Month: M, MM, MMM, MMMM, MMMMM
Day of month: d, dd
Day name of week: E, EEEE, EEEEE, EEEEEE

edited Dec 01 '22 at 08:59

Throvn

795
7
19

answered Sep 12 '18 at 14:24

BatyrCan

6,773
2
14
23

4

One of the best answer – Muhammad Abbas Apr 12 '21 at 11:45
3

See https://stackoverflow.com/a/55093100/1663987 for how to get the whole list. – simpleuser Jun 22 '21 at 00:01
1

I just run into one thing that might be useful for someone some day: there is an important difference between "YYYY" and "yyyy" dateFormats. "YYYY" will respect the year the week started at of the date: Jan 1, 2022 will actually display Jan 1, 2021 because that week started in 2021. This can be rather annoying to spot. Use "yyyy" as it is in this post. "YYYY" sounds to be useful in a particular scenario when you need to display the year the week started at as opposed to the actual year belongs to the date. – Gábor Hertelendy Aug 21 '22 at 07:25
Any one looking for another date formats check [this](http://www.unicode.org/reports/tr35/tr35-dates.html#8-date-format-patterns) – udi Sep 07 '22 at 05:32

LorenzOliveto · Accepted Answer · 2019-06-18T12:15:55.950

398

You have to declare 2 different NSDateFormatters, the first to convert the string to a NSDate and the second to print the date in your format.
Try this code:

let dateFormatterGet = NSDateFormatter()
dateFormatterGet.dateFormat = "yyyy-MM-dd HH:mm:ss"

let dateFormatterPrint = NSDateFormatter()
dateFormatterPrint.dateFormat = "MMM dd,yyyy"

let date: NSDate? = dateFormatterGet.dateFromString("2016-02-29 12:24:26")
print(dateFormatterPrint.stringFromDate(date!))

Swift 3 and higher:

From Swift 3 NSDate class has been changed to Date and NSDateFormatter to DateFormatter.

let dateFormatterGet = DateFormatter()
dateFormatterGet.dateFormat = "yyyy-MM-dd HH:mm:ss"

let dateFormatterPrint = DateFormatter()
dateFormatterPrint.dateFormat = "MMM dd,yyyy"

if let date = dateFormatterGet.date(from: "2016-02-29 12:24:26") {
    print(dateFormatterPrint.string(from: date))
} else {
   print("There was an error decoding the string")
}

edited Jun 18 '19 at 12:15

answered Feb 29 '16 at 13:08

LorenzOliveto

7,796
1
20
47

1

What happens if the dateFormatterGet dateFormat needs to accept 2 different formats - one containing milliseconds and one without milliseconds? ie yyyy-MM-dd'T'HH:mm:ssZZZZZ and yyyy-MM-dd'T'HH:mm:ss:SSSZZZZZ – KvnH Jul 24 '18 at 20:39
1

I think you have to declare two different DateFormatters to get the date: if the first one fails (it will return nil), use the second. – LorenzOliveto Jul 25 '18 at 06:34
Can you please help me, what will the date format for "Tue Mar 12 2019 12:00:00 GMT-0500 (CDT)" – Devesh.452 Mar 25 '19 at 16:17
1

@Devesh it should be something like this "EEE MMM d yyyy HH:mm:ss ZZZZ", check out https://nsdateformatter.com it's a very hanful site with all the formats supported – LorenzOliveto Mar 27 '19 at 15:55
@lorenzoliveto yes I have tried all the way for this format I tried on nsdateformatter.com too, still, I am not able to get anything for "Tue Mar 12 2019 12:00:00 GMT-0500 (CDT)" this format. I am getting this format in a JSON. I am not sure wether this is valid string, can you please help me. – Devesh.452 Mar 28 '19 at 15:37
@Devesh this should be the format you need "EEE MMM d yyyy HH:mm:ss 'GMT'Z '('z')'" – LorenzOliveto Mar 28 '19 at 16:15
@Devesh E MMM d yyyy HH:mm:ss 'GMT'Z will work for you – Manoj Feb 23 '20 at 22:42

score 102 · Answer 3 · edited Apr 11 '22 at 12:36

Swift - 5.0

let date = Date()
let format = date.getFormattedDate(format: "yyyy-MM-dd HH:mm:ss") // Set output format

extension Date {
   func getFormattedDate(format: String) -> String {
        let dateformat = DateFormatter()
        dateformat.dateFormat = format
        return dateformat.string(from: self)
    }
}

Swift - 4.0

2018-02-01T19:10:04+00:00 Convert Feb 01,2018

extension Date {
    static func getFormattedDate(string: String , formatter:String) -> String{
        let dateFormatterGet = DateFormatter()
        dateFormatterGet.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
        
        let dateFormatterPrint = DateFormatter()
        dateFormatterPrint.dateFormat = "MMM dd,yyyy"
        
        let date: Date? = dateFormatterGet.date(from: "2018-02-01T19:10:04+00:00")
        print("Date",dateFormatterPrint.string(from: date!)) // Feb 01,2018
        return dateFormatterPrint.string(from: date!);
    }
}

Jonas Deichelmann · Answer 4 · 2020-08-11T05:54:17.443

70

Swift 3 and higher

let dateFormatter = DateFormatter()
dateFormatter.dateStyle = .medium
dateFormatter.timeStyle = .none
dateFormatter.locale = Locale.current
print(dateFormatter.string(from: date)) // Jan 2, 2001

This is also helpful when you want to localize your App. The Locale(identifier: ) uses the ISO 639-1 Code. See also the Apple Documentation

edited Aug 11 '20 at 05:54

answered Nov 30 '17 at 20:08

Jonas Deichelmann

3,513
1
30
45

11

If you want to localize your app, just use `Locale.current` to use the user's locale. – Victor Engel Dec 28 '18 at 20:28

ciccioska · Answer 5 · 2017-12-18T15:05:54.327

37

Swift 3 version with the new Date object instead NSDate:

let dateFormatterGet = DateFormatter()
dateFormatterGet.dateFormat = "yyyy-MM-dd HH:mm:ss"

let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "MMM dd,yyyy"

let date: Date? = dateFormatterGet.date(from: "2017-02-14 17:24:26")
print(dateFormatter.string(from: date!))

EDIT: after mitul-nakum suggestion

edited Dec 18 '17 at 15:05

answered Feb 14 '17 at 16:44

ciccioska

1,291
16
22

2

dateFormatterGet.dateFormat = "yyyy-MM-dd HH:mm:ss" hour formate will require capital HH, as hour is in 24 formate – Mitul Nakum Aug 30 '17 at 09:08

Atikul Gazi · Answer 6 · 2020-10-27T17:31:01.527

Convert @BatyrCan answer to Swift 5.3 with extra formats. Tested in Xcode 12.

let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "HH:mm:ss"
var dateFromStr = dateFormatter.date(from: "12:16:45")!

dateFormatter.dateFormat = "hh:mm:ss a 'on' MMMM dd, yyyy"
//Output: 12:16:45 PM on January 01, 2000

dateFormatter.dateFormat = "E, d MMM yyyy HH:mm:ss Z"
//Output: Sat, 1 Jan 2000 12:16:45 +0600

dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
//Output: 2000-01-01T12:16:45+0600

dateFormatter.dateFormat = "EEEE, MMM d, yyyy"
//Output: Saturday, Jan 1, 2000

dateFormatter.dateFormat = "MM-dd-yyyy HH:mm"
//Output: 01-01-2000 12:16

dateFormatter.dateFormat = "MMM d, h:mm a"
//Output: Jan 1, 12:16 PM

dateFormatter.dateFormat = "HH:mm:ss.SSS"
//Output: 12:16:45.000

dateFormatter.dateFormat = "MMM d, yyyy"
//Output: Jan 1, 2000

dateFormatter.dateFormat = "MM/dd/yyyy"
//Output: 01/01/2000

dateFormatter.dateFormat = "hh:mm:ss a"
//Output: 12:16:45 PM

dateFormatter.dateFormat = "MMMM yyyy"
//Output: January 2000

dateFormatter.dateFormat = "dd.MM.yy"
//Output: 01.01.00

//Customisable AP/PM symbols
dateFormatter.amSymbol = "am"
dateFormatter.pmSymbol = "Pm"
dateFormatter.dateFormat = "a"
//Output: Pm

// Usage
var timeFromDate = dateFormatter.string(from: dateFromStr)
print(timeFromDate)

Ângelo Polotto · Answer 7 · 2019-03-07T12:44:01.777

I solved my problem to the format yyyy-MM-dd'T'HH:mm:ss.SSS'Z'(e.g 2018-06-15T00:00:00.000Z) with this:

func formatDate(date: String) -> String {
   let dateFormatterGet = DateFormatter()
   dateFormatterGet.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"

   let dateFormatter = DateFormatter()
   dateFormatter.dateStyle = .medium
   dateFormatter.timeStyle = .none
   //    dateFormatter.locale = Locale(identifier: "en_US") //uncomment if you don't want to get the system default format.

   let dateObj: Date? = dateFormatterGet.date(from: date)

   return dateFormatter.string(from: dateObj!)
}

iParesh · Answer 8 · 2017-05-01T05:07:50.817

30

swift 3

let date : Date = Date()
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "MMM dd, yyyy"
let todaysDate = dateFormatter.string(from: date)

edited May 01 '17 at 05:07

answered Feb 29 '16 at 13:36

iParesh

2,338
1
18
30

mahan · Answer 9 · 2022-08-05T08:50:22.793

21

iOS 15.0+

iPadOS 15.0+,

macOS 12.0+,

Mac Catalyst 15.0+,

tvOS 15.0+,

watchOS 8.0+,

Xcode 13.0+

Use formatted(date:time:)

let now = Date.now
let date = now.formatted(date: .abbreviated, time: .omitted)

Instead of .abbreviated, you may use another DateStyle such as .long, .numeric or define a custom format.

SwiftUI

 Text(myDate, format: Date.FormatStyle(date: .numeric, time: .omitted))

or simply use:

 Text(myDate, style: .date)

Reference

formatted(date:time:)

init(_:format:)

Text.DateStyle

edited Aug 05 '22 at 08:50

answered Jun 10 '21 at 14:19

mahan

12,366
5
48
83

1

The documentation says this is available in iOS 15, not related to Swift version. – Sulthan Dec 20 '21 at 10:13
This is the best new way according to [the WWDC 2021](https://developer.apple.com/videos/play/wwdc2021/10109/?time=871)! **If you want to have more flexibility you can use `.dateTime` inside `.formatted()`** instead of the `.formatted(date:time:)`. For example `.formatted(.dateTime.day().month())` will get you „Feb 29“. Check out the [Date.FormatStyle documentation](https://developer.apple.com/documentation/foundation/date/formatstyle) for more details. – alexkaessner Feb 21 '23 at 11:42

score 15 · Answer 10 · answered May 29 '22 at 07:59

Swift Version: 5.6 + Above

DateFormatter’s dateFormatter property is used to format Date with a custom String Pattern.

let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "MMM dd, yyyy"
    
let date = dateFormatter.string(from: datePicker.date)
print(date)
//Feb 28, 2022

If you want anything that shouldn’t be formatted and printed, then use single quotes around that word. Like; ‘at’

dateFormatter.dateFormat = "MMM dd, yyyy 'at' hh:MM a"
// May 29, 2022 at 12:05 PM

These are all possible Patterns to Format Date, Time & Time Zone.

not really, some put a "T" in before the time, not sure how that works. — John Pitts, Jan 26 '23 at 23:01

score 13 · Answer 11 · answered Aug 02 '19 at 11:40

13

Swift 4, 4.2 and 5

func getFormattedDate(date: Date, format: String) -> String {
        let dateformat = DateFormatter()
        dateformat.dateFormat = format
        return dateformat.string(from: date)
}

let formatingDate = getFormattedDate(date: Date(), format: "dd-MMM-yyyy")
        print(formatingDate)

answered Aug 02 '19 at 11:40

Akbar Khan

2,215
19
27

1

This is a good, short solution with just a single `DateFormatter()`! Something to be aware of: The `DateFormatter` also takes the application region (set in the scheme) into account! E.g. `2019-05-27 11:03:03 +0000` with the format `yyyy-MM-dd HH:mm:ss` and "Germany" as the region turns into `2019-05-27 13:03:03`. This difference is caused by DST: In summer Germany is GMT+2, while in winter it's GMT+1. – Neph Nov 22 '19 at 13:10
Superb answer! Good job. – beginner992 Jun 19 '21 at 09:18

score 11 · Answer 12 · answered Nov 12 '17 at 03:26

Swift 3 with a Date extension

extension Date {
    func string(with format: String) -> String {
        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = format
        return dateFormatter.string(from: self)
    }
}

Then you can use it like so:

let date = Date()
date.string(with: "MMM dd, yyyy")

score 7 · Answer 13 · answered Apr 12 '19 at 14:45

If you want to parse date from "1996-12-19T16:39:57-08:00", use the following format "yyyy-MM-dd'T'HH:mm:ssZZZZZ":

let RFC3339DateFormatter = DateFormatter()
RFC3339DateFormatter.locale = Locale(identifier: "en_US_POSIX")
RFC3339DateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
RFC3339DateFormatter.timeZone = TimeZone(secondsFromGMT: 0)

/* 39 minutes and 57 seconds after the 16th hour of December 19th, 1996 with an offset of -08:00 from UTC (Pacific Standard Time) */
let string = "1996-12-19T16:39:57-08:00"
let date = RFC3339DateFormatter.date(from: string)

from Apple https://developer.apple.com/documentation/foundation/dateformatter

Markus · Answer 14 · 2018-08-23T20:59:38.383

5

Another interessant possibility of format date. This screenshot belongs to Apple's App "News".

Here is the code:

let dateFormat1 = DateFormatter()
dateFormat1.dateFormat = "EEEE"
let stringDay = dateFormat1.string(from: Date())

let dateFormat2 = DateFormatter()
dateFormat2.dateFormat = "MMMM"
let stringMonth = dateFormat2.string(from: Date())

let dateFormat3 = DateFormatter()
dateFormat3.dateFormat = "dd"
let numDay = dateFormat3.string(from: Date())

let stringDate = String(format: "%@\n%@ %@", stringDay.uppercased(), stringMonth.uppercased(), numDay)

Nothing to add to alternative proposed by lorenzoliveto. It's just perfect.

let dateFormat = DateFormatter()
dateFormat.dateFormat = "EEEE\nMMMM dd"
let stringDate = dateFormat.string(from: Date()).uppercased()

edited Aug 23 '18 at 20:59

answered Aug 12 '18 at 09:32

Markus

1,147
16
26

This can be compacted using only one date formatter with the format "EEEE\nMMMM dd". – LorenzOliveto Aug 20 '18 at 09:44
RECTIFICATION: I have tested the code but you do not obtain the letters in uppercase. – Markus Aug 23 '18 at 11:55
1

Yes, the uppercase has to be applied to the string returned, like in your answer. The the date formatter doesn't return an uppercase string. Just add .uppercased() like this "dateFormat.string(from: Date()).uppercased()" – LorenzOliveto Aug 23 '18 at 12:50

score 5 · Answer 15 · answered Mar 19 '20 at 07:54

    import UIKit
    // Example iso date time
    let isoDateArray = [
        "2020-03-18T07:32:39.88Z",
        "2020-03-18T07:32:39Z",
        "2020-03-18T07:32:39.8Z",
        "2020-03-18T07:32:39.88Z",
        "2020-03-18T07:32:39.8834Z"
    ]


    let dateFormatterGetWithMs = DateFormatter()
    let dateFormatterGetNoMs = DateFormatter()

// Formater with and without millisecond 
    dateFormatterGetWithMs.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"
    dateFormatterGetNoMs.dateFormat = "yyyy-MM-dd'T'HH:mm:ss'Z'"

    let dateFormatterPrint = DateFormatter()
    dateFormatterPrint.dateFormat = "MMM dd,yyyy"

    for dateString in isoDateArray {
        var date: Date? = dateFormatterGetWithMs.date(from: dateString)
        if (date == nil){
            date = dateFormatterGetNoMs.date(from: dateString)
        }
        print("===========>",date!)
    }

While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value. — Piotr Labunski, Mar 19 '20 at 08:40

score 3 · Answer 16 · answered Feb 12 '19 at 05:32

just use below function to convert date format:-

  let convertedFormat =  convertToString(dateString: "2019-02-12 11:23:12", formatIn: "yyyy-MM-dd hh:mm:ss", formatOut: "MMM dd, yyyy")    //calling function

   print(convertedFormat) // feb 12 2019


 func convertToString (dateString: String, formatIn : String, formatOut : String) -> String {

    let dateFormater = DateFormatter()
    dateFormater.timeZone = NSTimeZone(abbreviation: "UTC") as TimeZone!
    dateFormater.dateFormat = formatIn
    let date = dateFormater.date(from: dateString)

    dateFormater.timeZone = NSTimeZone.system

    dateFormater.dateFormat = formatOut
    let timeStr = dateFormater.string(from: date!)
    return timeStr
 }

dasdom · Answer 17 · 2016-02-29T13:10:14.263

2

To convert 2016-02-29 12:24:26 into a date, use this date formatter:

let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd hh:mm:ss"

Edit: To get the output Feb 29, 2016 use this date formatter:

let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "MMM dd, yyyy"

edited Feb 29 '16 at 13:10

answered Feb 29 '16 at 13:05

dasdom

13,975
2
47
58

But how will you convert that to this kind of date format Feb 29, 2016 – Sydney Loteria Feb 29 '16 at 13:07
do you know why I get nil when I try to print this? – Pavlos May 15 '17 at 11:55

score 2 · Answer 18 · edited Sep 14 '20 at 08:58

Place it in extension and call it like below. It's easy to use throughout the application.

self.getFormattedDate(strDate: "20-March-2019", currentFomat: "dd-MMM-yyyy", expectedFromat: "yyyy-MM-dd")

Implementation

func getFormattedDate(strDate: String , currentFomat:String, expectedFromat: String) -> String{
    let dateFormatterGet = DateFormatter()
    dateFormatterGet.dateFormat = currentFomat

    let date : Date = dateFormatterGet.date(from: strDate) ?? Date()

    dateFormatterGet.dateFormat = expectedFromat
    return dateFormatterGet.string(from: date)
}

score 2 · Answer 19 · answered Mar 11 '20 at 19:58

For Swift 4.2, 5

Pass date and format as whatever way you want. To choose format you can visit, NSDATEFORMATTER website:

static func dateFormatter(date: Date,dateFormat:String) -> String {
    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = dateFormat
    return dateFormatter.string(from: date)
}

score 2 · Answer 20 · answered Oct 25 '21 at 15:08

From iOS 15 use something like this:

extension Date {
    var string: String {
        if #available(iOS 15.0, *) {
            return self.formatted(date: .complete, time: .complete)
        } else {
            return self.description
        }
    }
}

score 1 · Answer 21 · answered May 07 '22 at 09:27

Here is a full date format extension for swift

extension Date {
   func getFormattedDate(format: String) -> String {
        let dateformat = DateFormatter()
        dateformat.dateFormat = format
        return dateformat.string(from: self)
    }
    
    func getFormattedDate(style: DateFormatter.Style) -> String {
         let dateformat = DateFormatter()
         dateformat.dateStyle = style
         return dateformat.string(from: self)
     }
}

Usage

myDate.getFormattedDate(style: .medium) //medium, short, full, long

OR

myDate.getFormattedDate(format: "yyyy/MM/dd HH:mm:ss")

score 0 · Answer 22 · answered May 08 '17 at 17:48

swift 3

func dataFormat(dataJ: Double) -> String {

        let dateFormatter = DateFormatter()
        dateFormatter.dateStyle = .long
        dateFormatter.timeStyle = .none
        let date = Date(timeIntervalSince1970: dataJ)
        return (dataJ != nil) ? "Today, \(dateFormatter.string(from: date))" : "Date Invalid"

    }

score 0 · Answer 23 · answered Apr 30 '20 at 09:31

I recommend to add timezone by default. I will show an example for swift 5
1. new an extension file Date+Formatter.swift

import Foundation

extension Date {
    func getFormattedDateString(format: String) -> String {
        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = format
        dateFormatter.timeZone = TimeZone.current
        return dateFormatter.string(from: self)
    }
}

Usage example

    let date = Date()
    let dateString = date.getFormattedDateString(format: "yyyy-MM-dd HH:mm:ss")
    print("dateString > \(dateString)")
    // print
    // dateString > 2020-04-30 15:15:21

yoAlex5 · Answer 24 · 2023-04-25T14:27:20.610

Swift Date

Date <-> Formatter <-> String

Date

Date:

single point in time (UTC). It means that it doesn't contain any TimeZone or other metadata
Is a kind of wrapper of Double - seconds from 2001-01-01 00:00:00 +0000

Date(timeIntervalSinceReferenceDate: .zero)

print output of Date in UTC(+0000) is in ISO 8601(ISO8601DateFormatter yyyy-MM-dd'T'HH:mm:ssZ)

Create Date:

current time in UTC Date()
from String using Formatter and TimeZone

func strToDateWithLocalTimeZone(_ str: String, format: String) -> Date {
    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = format
    dateFormatter.locale = Locale(identifier: "en_US_POSIX")
//        dateFormatter.timeZone = .current //by default
//        dateFormatter.timeZone = TimeZone(abbreviation: "UTC")
    
    return dateFormatter.date(from: str)!
}

Formatter

It is responsible for format date and have two main functions:

Date -> String: .string(from: Date)
String -> Date: .date(from: String)

Main parts:

Formatter.dateFormat
- Custom: yyyy-MM-dd, dd.MM.yyyy HH:mm:ss...
- ISO8601DateFormatter: yyyy-MM-dd'T'HH:mm:ssZ
Formatter.TimeZone
- Formatter.TimeZone = .current is set by default. It means if you don't setup it explicitly local TimeZone will be used by default
- Local aka Current TimeZone is defined by System and your settings. Also it is different for specific Date. It means that when you use Formatter.TimeZone.current for Date with different time shift - value will be different(for current TimeZone)
```
//TimeZone in Settings
Settings -> General -> Date & Time -> Time Zone
```
```
//Date -> String
2022-12-31T22:59:59+02:00
2023-04-04T21:01:34+03:00
```
- Specific. TimeZone(abbreviation: "CET") == TimeZone(secondsFromGMT: 3600) (3600 seconds == 1 hour). UTC. TimeZone(abbreviation: "UTC")...

String

If String doesn't contain TimeZone you are able to set TimeZone in Formatter
When String contains TimeZone - it means that it is a single variant of interpret the String in Date UTC that is why Formatter.TimeZone will not have any effect

String <date_with_time_zone> -> Format <any_time_zome> -> single Date
String: 09.04.2023T18:58:32+0300 -> Format <any_time_zome> -> Date: 2023-04-09 15:58:32 +0000

Experiments:

My Local time:

let dateFormatStr = "dd.MM.yyyy'T'HH:mm:ssZ"

//Current TimeZone
let currentTimeZone = TimeZone.current
let seconds = currentTimeZone.secondsFromGMT()
let hours = seconds/3600
let minutes = abs(seconds/60) % 60
print("current TimeZone: \(String(format: "%+.2d:%.2d", hours, minutes)) for:\(currentTimeZone)")
//        current TimeZone: +03:00 for:Europe/Kiev (fixed (equal to current))

//Current Date
let currentDate = Date()
print("current Date UTC: \(currentDate)")
//        current Date UTC: 2023-04-09 15:58:32 +0000

//Date -> String
let dateFormatter = DateFormatter()
dateFormatter.locale = Locale(identifier: "en_US_POSIX")
dateFormatter.dateFormat = dateFormatStr
dateFormatter.timeZone = .current //by default. Adds +0300 in my case at the end of string
let currentDateStr = dateFormatter.string(from: currentDate)
print("current DateString Local: \(currentDateStr)")
//        current DateString Local: 09.04.2023T18:58:32+0300

//String to Date
let dateFormatterLocal = DateFormatter()
dateFormatterLocal.locale = Locale(identifier: "en_US_POSIX")
dateFormatterLocal.dateFormat = dateFormatStr
dateFormatterLocal.timeZone = .current //by default. Doesn't have effect when String contains TimeZone

let dateLocal = dateFormatterLocal.date(from: currentDateStr)!
print("current Date Local: \(dateLocal)")
//        current Date Local: 2023-04-09 15:58:32 +0000

Output in a single place

current TimeZone: +03:00 for:Europe/Kiev (fixed (equal to current))
current Date UTC: 2023-04-09 15:58:32 +0000
current DateString Local: 09.04.2023T18:58:32+0300
current Date Local: 2023-04-09 15:58:32 +0000

Some real use case:

Client make a transaction
Send Date to Server as String
Get Date from Server as String
Show Date as String in:

UTC
Local TimeZone
Transaction TimeZone

1. Client make a transaction
Date()
Formatter.timeZone = .current
String: 09.04.2023 18:58:32+0300

2. Send Date to Server as String
09.04.2023 18:58:32+0300

3. Get Date from Server as String 
09.04.2023 18:58:32+0300

4. Show Date

- UTC TimeZone
String -> Date -> Formatter.timeZone = UTC -> String
UTC: 09.04.2023 15:58:32+0000

- Local TimeZone(Depends where you are)
String -> Date -> Formatter.timeZone = .current -> String
For example Local timezone will be different: 
    if you now at +0100 TimeZone 09.04.2023 16:58:32+0100
    if you now at +0200 TimeZone 09.04.2023 17:58:32+0200

- Transaction TimeZone
remove +0300 from String. It is a workaround, and not a clear solution but as is: 09.04.2023 18:58:32 

String -> Formatter.timeZone = UTC -> Date: 09.04.2023 18:58:32+0000
Date -> Formatter.timeZone = UTC -> String: 09.04.2023 18:58:32+0000

score -1 · Answer 25 · answered Feb 04 '22 at 05:54

class Utils {
  class func dateFormatter(_ date: Date, _ format: String) -> String {
    let dateformat = DateFormatter()
    dateformat.dateFormat = format
    return dateformat.string(from: date)
  }
}
print(Utils.dateFormatter(Date(), "EEEE, MMM d, yyyy"))

Create class name Utils import same function and you can use globally accesss any where with your date and formate