Calculate age from birth date using NSDateComponents in Swift

Question

I am trying calculate the age from birthdayDate in Swift with this function:

var calendar : NSCalendar = NSCalendar.currentCalendar()  var dateComponentNow : NSDateComponents = calendar.components(              NSCalendarUnit.CalendarUnitYear,               fromDate: birthday,               toDate: age,               options: 0) 

But I get an error Extra argument toDate in call

In objective c this was the code, but I don't know why get this error:

NSDate* birthday = ...;  NSDate* now = [NSDate date]; NSDateComponents* ageComponents = [[NSCalendar currentCalendar]                                 components:NSYearCalendarUnit                                 fromDate:birthday                                toDate:now                                options:0]; NSInteger age = [ageComponents year];  

Is there correct form better than this?

Answer 1

You get an error message because 0 is not a valid value for NSCalendarOptions. For "no options", use NSCalendarOptions(0) or simply nil:

let ageComponents = calendar.components(.CalendarUnitYear,                               fromDate: birthday,                                 toDate: now,                                options: nil) let age = ageComponents.year 

(Specifying nil is possible because NSCalendarOptions conforms to the RawOptionSetType protocol which in turn inherits from NilLiteralConvertible.)

Update for Swift 2:

let ageComponents = calendar.components(.Year,     fromDate: birthday,     toDate: now,     options: []) 

Update for Swift 3:

Assuming that the Swift 3 types Date and Calendar are used:

let now = Date() let birthday: Date = ... let calendar = Calendar.current  let ageComponents = calendar.dateComponents([.year], from: birthday, to: now) let age = ageComponents.year!