How can I parse / create a date time stamp formatted with fractional seconds UTC timezone (ISO 8601, RFC 3339) in Swift?

Question

How to generate a date time stamp, using the format standards for ISO 8601 and RFC 3339?

The goal is a string that looks like this:

\"2015-01-01T00:0         


        

Answer 1

Swift 5

If you're targeting iOS 11.0+ / macOS 10.13+, you simply use ISO8601DateFormatter with the withInternetDateTime and withFractionalSeconds options, like so:

let date = Date()

let iso8601DateFormatter = ISO8601DateFormatter()
iso8601DateFormatter.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
let string = iso8601DateFormatter.string(from: date)

// string looks like "2020-03-04T21:39:02.112Z"