Swift date formatting with NSDateFormatter

Question

i have a json object that contains a date from database:

var showDateRaw = v["feedDate"].description
println(showDateRaw)

showDateRaw variable's type is String and looks like this way after parsing the json object: 2015-05-10T18:39:55+02:00

i would like to convert it to look like this way: 2015.05.10 - 18:39

First of all i was trying to convert to NSDate with NSDateFormatter:

 var formatter : NSDateFormatter = NSDateFormatter()
    formatter.dateFormat = "yyyy'-'MM'-'dd'T'HH':'mm':'ss'Z'"
    let dateShow = formatter.dateFromString(v["feedDate"].description)
    println(dateShow)

And then somehow convert this date to the new format and then convert it to String. But when i try to print the formated dateShow variable it's value is nil..

Could anybody help me how can i convert this String date to a expected format?

Thank you very much!

By the answers i've tried this way:

var formatter = NSDateFormatter()
            formatter.dateFormat = "yyyy'-'MM'-'dd'T'HH':'mm':'ss'Z'"
            let dateShow = formatter.dateFromString(v["feedDate"].description)
            var finalFormatter = NSDateFormatter()
            finalFormatter.dateFormat = "yyyy.MM.dd HH:mm"
            let finalDate = finalFormatter.stringFromDate(dateShow!)

but it throws an error:

fatal error: unexpectedly found nil while unwrapping an Optional value

do you have any idea why is it? Thank you..

UPDATE:

this is the solution, my json parser api had a .asDate method which return with optional NSDate.

let dateShow : NSDate? = v["feedDate"].asDate
            var finalFormatter = NSDateFormatter()
            finalFormatter.dateFormat = "yyyy.MM.dd - HH:mm"
            let finalDate = finalFormatter.stringFromDate(dateShow!)
            println(finalDate)

After got it, it was easy to convert to expected format.

Thank you very much for every idea!

Answer 1

You need to reformat the date you retrive from the JSON to the format you want to use:

var formatter = NSDateFormatter()
formatter.dateFormat = "yyyy'-'MM'-'dd'T'HH':'mm':'ss'Z'"
let dateShow = formatter.dateFromString(v["feedDate"].description)
var finalFormatter = NSDateFormatter()
finalFormatter.dateFormat = "yyyy.MM.dd - HH:mm"
let finalDate = finalFormatter.stringFromDate(dateShow)

I Hope that helps you!

Answer 2

let dateShow = formatter.dateFromString(v["feedDate"].description)

I would first check if v["feedDate"] isn't an optional, because in this case the v["feedDate"].description would probably contain string like

Optional("2015-05-10T18:39:55+02:00") as opposed to 2015-05-10T18:39:55+02:00 ,

which obviously won't get converted to NSDate...

Edit: Under your original post you provided this information:

this is what it's print: 2015-05-27T12:51:28.27+02:00 but if i do this way: println(v["feedDate"].asDate) it's print this: Optional(2015-05-23 14:57:43 +0000) i'm using this repo for parsing json

You can use this format in NSDateFormatter to parse it:

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

It looks like the API you are using actually already knows how to make a date of it with the asDate method. In any case, if you use your own formatter, make sure that you pass the right string to it, not a description of a String?.