ios - DateFormatter producing unexpected result on device -

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• nsdateformatter show wrong year 1 answer

i have following code:

var components = datecomponents() components.year = 2017 components.month = 1  var calendar = calendar.current let date = calendar.date(from: components)!  let formatter = dateformatter() formatter.setlocalizeddateformatfromtemplate("mmmmyyyy") let string = formatter.string(from: date) 

when run in simulator on computer works expect , value of string january 2017.

however, when run same code on device value of string january 2016. can causing difference?

the difference

• a different locale on device , simulator.

and / or

• yyyy year in week of year based calendar.
• yyyy year in standard calendar.

you should use yyyy.