获取当前日期时间、日期时间格式化及转换

转自：http://blog.csdn.net/ooppookid/article/details/42506957

1.获取当前日期时间

var nowDate = NSDate()
var formatter = NSDateFormatter()
formatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
var dateString = formatter.stringFromDate(nowDate)
println(dateString)

2.字符串转换日期时间

var dateString1 = "2014-1-7"
var formatter1 = NSDateFormatter()
formatter1.dateFormat = "yyyy-M-d"
var date1 = formatter1.dateFromString(dateString1)
println(date1)

3.日期时间转换字符串

var date2 = NSDate()
var formatter2 = NSDateFormatter()
formatter2.dateFormat = "yyyy-MM-dd"
var dateString2 = formatter2.stringFromDate(date2)
println(dateString2)