The way I did this in Swift 2.3 was:
let currentDate = NSDate() let currentCalendar = NSCalendar.currentCalendar() var startDate : NSDate? var e
In Swift 4 there is a simple one-liner to get the number of days (or any other DateComponent) between two dates:
let diffInDays = Calendar.current.dateComponents([.day], from: dateA, to: dateB).day