Generally the most used in the normal situation is to get the date and format project.
1, only hours, minutes, the seconds personally feel that using the following code
dateFormater = NSDateFormatter the let ()
dateFormater.dateFormat = "HH: mm: SS"
the let Time = dateFormater.stringFromDate (currentDate)
2, also need to be the date when using the following codes (because the first month is a way to get English)
let currentDate = NSDate()
let calendar = NSCalendar.currentCalendar()
let dateComponents = calendar.components([NSCalendarUnit.Year, NSCalendarUnit.Month, NSCalendarUnit.Day, NSCalendarUnit.Hour, NSCalendarUnit.Minute, NSCalendarUnit.Second], fromDate: currentDate)
print(dateComponents.year)
print(dateComponents.month)
print(dateComponents.day)
print(dateComponents.hour)
print(dateComponents.minute)
print(dateComponents.second)
3、将字符串转化为日期
dateFormatter = NSDateFormatter the let ()
dateFormatter.dateFormat = "the MM-dd-YYYY HH: mm: SS"
var dateAsString = "2015-10-08 14:25:37"
the let date1 = dateFormatter.dateFromString (dateAsString)
. 4, Comparative Date interval (this feature is often used)
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
var dateAsString = "2015-10-08 14:25:37"
let date1 = dateFormatter.dateFromString(dateAsString)!
dateAsString = "2018-03-05 08:14:19"
let date2 = dateFormatter.dateFromString(dateAsString)!
var diffDateComponents = NSCalendar.currentCalendar().components([NSCalendarUnit.Year, NSCalendarUnit.Month, NSCalendarUnit.Day, NSCalendarUnit.Hour, NSCalendarUnit.Minute, NSCalendarUnit.Second], fromDate: date1, toDate: date2, options: NSCalendarOptions.init(rawValue: 0))
print("The difference between dates is: (diffDateComponents.year) years, (diffDateComponents.month) months, (diffDateComponents.day) days, (diffDateComponents.hour) hours, (diffDateComponents.minute) minutes, (diffDateComponents.second) seconds")