From an API I get the following two date strings. Those dates show the time of a weather observation of a weather station that’s located in some time zone.
dateUTC = "2019-06-14T18:00:00Z"
dateLocal = "2019-06-14 20:00:00"
How can I determine the time zone the weather station is in?
(Not the time zone of the user!)
I've tried to use the DateFormatter, but unfortunately the local date gets immediately transformed to GMT - and it's then identical with the UTC date.
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
let dateUTC = dateFormatter.date(from: current.currentObservation[0].timeUTC)!
dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
let dateLocal = dateFormatter.date(from: current.currentObservation[0].timeLocal)!
I would like to see as the result of the above date(s):
Time zone = GMT+2
The answer was quite simple - still I didn't see it for hours. The trick is to set a timeZone for the DateFormatter.
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
let dateUTC = dateFormatter.date(from: current.currentObservation[0].timeUTC)!
dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
dateFormatter.timeZone = TimeZone(abbreviation: "UTC")
let dateLocal = dateFormatter.date(from: current.currentObservation[0].timeLocal)!
let difference = Calendar.current.dateComponents([.second], from: dateUTC, to: dateLocal).second!
Related
I am using this function to convert UTC time to my local time stamp.
func UTCToLocal(date:String, timeZone: String) -> String {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "H:mm:ss"
dateFormatter.timeZone = TimeZone(abbreviation: "UTC")
let dt = dateFormatter.date(from: date)
dateFormatter.timeZone = TimeZone(identifier: timeZone)
dateFormatter.dateFormat = "h:mm a"
return dateFormatter.string(from: time)
}
But this doesn't check DST. So, I am getting one hour difference. Can anyone help me with some general solution for this problem?
Thanks to Leo who have figured out the issue. I have updated the functions as:
func UTCToLocal(date:String, timeZone: String) -> String {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"
dateFormatter.locale = Locale(identifier: "en_US_POSIX")
dateFormatter.timeZone = TimeZone(secondsFromGMT: 0)
let dt = dateFormatter.date(from: date)
dateFormatter.timeZone = TimeZone(identifier: timeZone)
dateFormatter.dateFormat = "dd-MM-yyyy hh:mm aa"
return dateFormatter.string(from: dt!)
}
Now the date string in function paramter have value in this format "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'". This solves the issue.
The issue here is the lack of the date. You are always passing only the time components without the day so the daylight savings time Will always be correspondent to January 1st 2001. If you need today’s date you need to set the date formatter defaultDate property to the startOfDay for today. Btw don’t forget to set the locale first to “en_US_POSIX” before setting the fixed date format.
I am using swift 4. I need to convert my UTC Time to local time.But it shows two hour before. I am now Living in dhaka with GMT+6. Here is code i used ..
var date:String = "2020-02-10 14:30:57 PM"
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd H:mm:ss a"
dateFormatter.timeZone = TimeZone(abbreviation: "UTC")
let dt = dateFormatter.date(from: date)
dateFormatter.timeZone = TimeZone.current
dateFormatter.dateFormat = "yyyy-MM-dd h:mm a"
let convertedLocalTime = dateFormatter.string(from: dt!)
tv_time.text = convertedLocalTime
print("convertedLocalTime-->",convertedLocalTime)
It shows 2020-02-10 6:30 PM But now 8.30 PM . What is the wrong with the code
Please help me
Your input data is not correctly formatted.
If you can use a correct format for the input data:
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd H:mm:ss"
dateFormatter.timeZone = TimeZone(abbreviation: "UTC")
// set the date in UTC
let date = dateFormatter.date(from: "2020-02-10 14:30:57")
dateFormatter.timeZone = TimeZone.current
// String representation of the date for local time
let s = dateFormatter.string(from: date!)
this snippet sets s to "2020-02-10 15:30:57" which is correct for Germany.
Otherwise you have to correct the format of your input data, e.g. delete the "PM" from the 24h format string.
How can I parse a date that has only date information (without time), like 2018-07-24
Im trying with
let dateFormatter = DateFormatter()
dateFormat.dateFormat = "yyyy-MM-dd"
dateFormatter.dateFormat = dateFormat
dateFormatter.timeZone = TimeZone(abbreviation: "UTC")
dateFormatter.date(from: "2018-07-24")
prints day 23
It looks like it uses 00:00:00 as default time and then transform it into UTC results into the day before...
How can I change that?
Seems that you set time zone for formatter to UTC but then try to get the day in your local time zone.
If you use this code - you will see the 24-th day
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd"
dateFormatter.timeZone = TimeZone(abbreviation: "UTC")
let date = dateFormatter.date(from: "2018-07-24")
print(dateFormatter.string(from: date!)) // prints "2018-07-24"
But if you use "Calendar" to get the day component from the date you will get the day with your timeZone offset.
So for example in my time zone I see the 24th day (GMT+02) using this code
var calendar = Calendar.current
let day = calendar.component(.day, from: date!)
print(day) // prints 24
But if I set the time zone for calendar somewhere in USA I see the 23rd day
var calendar = Calendar.current
calendar.timeZone = TimeZone.init(abbreviation: "MDT")!
let day = calendar.component(.day, from: date!)
print(day) // prints 23
So the calendar uses your local time zone to get the component from date
So if you need to get the day component from date use the same time zone you used to parse the date from string.
var calendar = Calendar.current
calendar.timeZone = TimeZone(abbreviation: "UTC")!
let day = calendar.component(.day, from: date!)
print(day) // prints 24
I have CEST dates in yyyy-MM-ddTHH:mm:ssZ format. I want to show them in local format. The following function works fine. It shows the time correctly.
But in the end I am forced to show the date in "dd.MM.yyyy HH:mm" format. How can i get Local/native DateFormat from iOS.
func changeTime()
{
myLabel.text = convertTimeZoneToLocal(timeZone: "CEST", date: "2017-09-27T18:25:42Z")
}
func convertTimeZoneToLocal(timeZone:String, date:String) -> String {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
dateFormatter.timeZone = TimeZone(abbreviation: timeZone)
let dt = dateFormatter.date(from: date)
dateFormatter.timeZone = TimeZone.current
dateFormatter.dateFormat = "dd.MM.yyyy HH:mm" // I want to change this line.
return dateFormatter.string(from: dt!)
}
You can use :
dateFormatter.dateStyle = .short
dateFormatter.timeStyle = .short
But these won't come in the same format dd.MM.yyyy HH:mm
// create dateFormatter with UTC time format
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss"
dateFormatter.timeZone = NSTimeZone(name: "UTC")
let date = dateFormatter.dateFromString("2015-04-01T11:42:00")// create date from string
// change to a readable time format and change to local time zone
dateFormatter.dateFormat = "EEE, MMM d, yyyy - h:mm a"
dateFormatter.timeZone = NSTimeZone.localTimeZone()
let timeStamp = dateFormatter.stringFromDate(date!)
Use this to get the the formate base on selected region of OS
let dateformatter = DateFormatter()
dateformatter.setLocalizedDateFormatFromTemplate("dd/MM/yyyy")
let strDate = dateformatter.string(from: NSDate() as Date)
Output :
OS Region is US : 18/02/2021
OS Region is US : 02/18/2021
I am trying to convert a UTC time to local timezone, but it doesn't seem to be converting it at all:
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZ"
let date1 = dateFormatter.dateFromString(dateStringFromServer)!
dateFormatter.timeZone = NSTimeZone.localTimeZone()
let date2 = dateFormatter.dateFromString(dateStringFromServer)!
The dateStringFromServer is a string representation of a UTC date. So I was expecting date1 to be in UTC, and date2 to be in PDT (my local time zone), but they are both the same. Something wrong with my syntax?
This is what I'm getting:
dateStringFromServer: 2016-10-21T05:24:26.000Z
date1: 2016-10-21 05:24:26 +0000
date2: 2016-10-21 05:24:26 +0000
How can I get date2 be in the device's local timezone?
If you want to convert to the time zone set on the device you can do this
Swift3
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZ"
let date1 = dateFormatter.date(from: dateStringFromServer)
// return the timeZone of your device i.e. America/Los_angeles
let timeZone = TimeZone.autoupdatingCurrent.identifier as String
dateFormatter.timeZone = TimeZone(identifier: timeZone)
let date2 = dateFormatter.string(from: date1)
Swift2
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZ"
let date1 = dateFormatter.dateFromString(dateStringFromServer)
// return the timeZone of your device i.e. America/Los_angeles
let timeZone = NSTimeZone.localTimeZone().name
dateFormatter.timeZone = NSTimeZone(name: timeZone)
let date2 = dateFormatter.stringFromDate(date1!)
It's the same because even though you think you're setting the date formatter's time zone to the current time zone after setting the first date, it doesn't matter. If you don't set the date formatter's time zone, it automatically sets to the system time zone as specified in Apple's docs for NSDateFormatter:
If unspecified, the system time zone is used.
Therefore the date formatter's time zone is set to be the same both implicitly for the first date and explicitly for the second date because they happen to be identical, hence you're getting the same date back.
Here is the code that work in swift4.
func UTCToLocal(date:String, fromFormat: String, toFormat: String) -> String {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = fromFormat
dateFormatter.timeZone = TimeZone(abbreviation: "UTC")
let dt = dateFormatter.date(from: date)
dateFormatter.timeZone = TimeZone.current
dateFormatter.dateFormat = toFormat
return dateFormatter.string(from: dt!)
}
How to use :-
let localDateAsString = UTCToLocal(date: deadline!, fromFormat: "yyyy-MM-dd HH:mm:ss", toFormat: "MM-dd-yyyy hh:mm a")