ISO string to CST javascript

Question

I have a date in the format of ISO string

date = new Date ().toISOString()

which returns me "2015-12-08T14:03:36.129Z"

now i want to change this date to CST and want output like

December 23, 2015 11: 30 AM

you should take a look here: http://stackoverflow.com/a/8047891/1114934 — ivan.mylyanyk, Dec 08 '15 at 14:06
Possible duplicate of [How do I get a UTC Timestamp in JavaScript?](http://stackoverflow.com/questions/9756120/how-do-i-get-a-utc-timestamp-in-javascript) — Blake Yarbrough, Dec 08 '15 at 14:23
Like on deamentiaemundi's answer, I can't recommend [moment](http://momentjs.com/) enough. It is the de facto datetime library for JS, both client and server side. — paolobueno, Dec 08 '15 at 17:58

score 1 · Answer 1 · answered Dec 09 '15 at 04:32

Note that CST is a single time zone that is UTC-0600. If you want daylight saving in the same zone, you'll need to program that yourself.

To get the time in any time zone, you can adjust the date's UTC time for the required offset, then just read the UTC values, like the following:

function getCST(date) {
  var months = ['January','February','March','April','May','June','July',
                'August','September','October','November','December'];
  var d = new Date(+date);
  
  // CST is UTC -0600 so subtract 6 hours and use UTC values
  d.setUTCHours(d.getUTCHours() - 6);
  
  return months[d.getUTCMonth()] + ' ' +
         d.getUTCDate() + ', ' +
         d.getUTCFullYear() + ' ' +
         ((d.getUTCHours()%12) || 12) + ':' +
         ('0' + d.getUTCMinutes()).slice(-2) + ' ' +
         (d.getUTCHours() < 12? 'AM':'PM');
}

document.write("Current CST time is: " + getCST(new Date()));

deamentiaemundi · Answer 2 · 2015-12-08T17:56:09.190

You can just format it yourself (assuming CST = north american central standard time = UTC - 6 hours)

function getCSTDate(){
  var months = ["January","February","March","April","May","June",
                "July","August","September","October","November","December"];
  var date = new Date();
  var meridian;
  var cstdate = "";

  date = new Date(
    date.getUTCFullYear(),
    date.getUTCMonth(),
    date.getUTCDate(),
    date.getUTCHours() - 6,
    date.getUTCMinutes(),
    date.getUTCSeconds(),
    date.getUTCMilliseconds()
  );
  meridian = (date.getHours() < 12)?"AM":"PM";
  //CST date example: December 23, 2015 11:30 AM
  cstDate =   months[date.getMonth()]
            + " "
            + date.getDate()
            + ", "
            + date.getFullYear()
            + " "
            + date.getHours()
            + ":"
            + date.getMinutes()
            + " "
            + meridian;

  return cstDate;
}

Obvious Problem with this approach: daylight saving time. You can do it by hand (doesn't change very often) or use something like TimezoneJS or MomentJS-timezone.

The new date can be set to 6 hours earlier simply by `date.setUTCHours(date.getUTCHours() - 6)`. But daylight saving boundaries will be an issue… — RobG, Dec 08 '15 at 23:29
@RobG Yepp, that's shorter, admitted ;-) But I work on dates (no, that are fruits, datums?) as little as possible and I know why: too many chances to leave that scene with a perforated foot, way too many! I use a build-in function or a library if available and MomentJS seems to be a good solution for JavaScript. — deamentiaemundi, Dec 08 '15 at 23:58

ISO string to CST javascript

2 Answers2