Convert UTC date to local date swift4 - ios

Question

All,
I am trying to convert UTC date to local date . Below is my code. But, even after converting I get both dates in UTC only.
static func getTodayDateInLocalTimeZone() -> Date{
let todaydateInUTC = Date()
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
dateFormatter.timeZone = TimeZone(identifier: "UTC")
let utcDateString = dateFormatter.string(from: todaydateInUTC)
print("Date::: utcDateString: \(utcDateString)")
// Changing to Current timezone
let timzoneIdentiier = TimeZone.current.identifier
let timezone = TimeZone(identifier: timzoneIdentiier)
let abbrv = timezone?.abbreviation()
let dateFormatter1 = DateFormatter()
dateFormatter1.timeZone = TimeZone(identifier: abbrv!)
dateFormatter1.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
print("Date:::timeZone: \(timzoneIdentiier) == \(String(describing: abbrv))")
let formattedDate1 = dateFormatter1.date(from: utcDateString)
print("Date:::: \(formattedDate1)")
return formattedDate1!
}
Here is what I get when I print
Date::: utcDateString: 2021-01-20T17:39:15+0000
Date:::timeZone: America/New_York == Optional("EST")
Date:::: Optional(2021-01-20 17:39:15 +0000)
Please let me know why is it now changing to the local timezone.
Thanks

Answer 1

First of all, a date does not have a time zone.
So let todaydateInUTC = Date() actually means let todaydate = Date().
The time zone becomes relevant, when you want to present a date to the user.
So instead of creating a new date from a the utcDateString, you just need to create another date string from the same date variable.
let formattedDate1 = dateFormatter1.date(from: utcDateString) becomes let tzDateString = dateFormatter1.string(from: todaydate).
This also means your function should return a string instead of a date.
For example:
func getTodayDateInLocalTimeZone() -> String
{
let now = Date()
// Just for debugging. Not for the result.
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
dateFormatter.timeZone = TimeZone(identifier: "UTC")
let utcDateString = dateFormatter.string(from: now)
print("Date::: utcDateString: \(utcDateString)")
let tz = TimeZone.current
let dateFormatter1 = DateFormatter()
dateFormatter1.timeZone = tz
dateFormatter1.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
print("Date:::timeZone: \(tz) == \(String(describing: tz.abbreviation()))")
let tzDateString = dateFormatter1.string(from: now)
print("Date:::: \(tzDateString)")
return tzDateString
}
For me it results in:
Date::: utcDateString: 2021-01-20T18:19:44+0000
Date:::timeZone: Europe/Berlin (current) == Optional("CET")
Date:::: 2021-01-20T19:19:44+0100