Convert date string swift

问题:

I have a date string in this format:

2016-06-20T13:01:46.457+02:00

and I need to change it to something like this:

20/06/2016

Previously I have always used this library -> SwiftDate to manipulate the dates, but it doesn't work now.

I tried also something like:

let myDate = self.dateNoteDict[indexPath.row]!
    let dateFormatter = NSDateFormatter()
    dateFormatter.dateFormat = "yyyy-MM-dd hh:mm:ss.SSSSxxx"
    let date = dateFormatter.dateFromString(myDate)
    print("date -> \(date)")

but it doesn't work. How can I do?

Thanks in advance.

回答1:

The standard ISO8601 date format with fractional seconds and time zone is

yyyy-MM-dd'T'HH:mm:ss.SSSZ

let myDate = "2016-06-20T13:01:46.457+02:00"
let dateFormatter = NSDateFormatter()
dateFormatter.locale = NSLocale(localeIdentifier: "en_US_POSIX") // edited
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZ"
let date = dateFormatter.dateFromString(myDate)!
dateFormatter.dateFormat = "dd/MM/yyyy"
let dateString = dateFormatter.stringFromDate(date)

Swift 3:

let myDate = "2016-06-20T13:01:46.457+02:00"
let dateFormatter = DateFormatter()
dateFormatter.locale = Locale(identifier: "en_US_POSIX") // edited
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZ"
let date = dateFormatter.date(from:myDate)!
dateFormatter.dateFormat = "dd/MM/yyyy"
let dateString = dateFormatter.string(from:date)

In macOS 10.13+, iOS 11+ ISO8601DateFormatter is an alternative as input formatter

let myDate = "2016-06-20T13:01:46.457+02:00"
let inputFormatter = ISO8601DateFormatter()
inputFormatter.formatOptions = [.withFullDate, .withFullTime, .withFractionalSeconds]
let date = dateFormatter.date(from:myDate)!
let outputFormatter = DateFormatter()
outputFormatter.locale = Locale(identifier: "en_US_POSIX")
outputFormatter.dateFormat = "dd/MM/yyyy"
let dateString = dateFormatter.string(from:date)

回答2:

I always use this code while converting String to Date . (Swift 3)

extension String
{
     func  toDate( dateFormat format  : String) -> Date
    {
        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = format
        if let date = dateFormatter.date(from: self)
        {
            return date
        }
        print("Invalid arguments ! Returning Current Date . ")
        return Date()
    }
}

and just call like . .

print ( "2016-06-20T13:01:46.457+02:00".toDate(dateFormat: "yyyy-MM-dd'T'HH:mm:ss.SSSZ") )
//Capital HH for 24-Hour Time