2015.02.13[Swift] NSDateからISO8601形式の文字列をつくる

ISO8601

JSONの日時表記に使ったりするので

let now = NSDate() // => Feb 13, 2015, 4:05 PM"
let iso8601Formatter = NSDateFormatter()
iso8601Formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
iso8601Formatter.stringFromDate(now) // => 2015-02-13T16:05:32+09:00

UTC固定なら timezone を設定

let now = NSDate() // => Feb 13, 2015, 4:05 PM"
let iso8601UTCFormatter = NSDateFormatter()
iso8601UTCFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss'Z'"
iso8601UTCFormatter.timeZone = NSTimeZone(forSecondsFromGMT: 0)
iso8601UTCFormatter.stringFromDate(now) // => 2015-02-13T07:05:32Z

参考

• ISO 8601 – Wikipedia
• Date Formatters – iOS Developer Library