How to convert DateTime into different timezones?

DateTime doesn't contain timezone information therefore you can't create a DateTime in a specific timezone only the timezone of your system and UTC are available.

You can wrap the DateTime in a custom class and add timezone information to the wrapper. You also need a table of offsets for each timezone and then add/substract the offset from the UTC date.

I wrote a package for this. It's called Instant, and it can convert a DateTime in any given timezone worldwide. Take a detailed look at https://aditya-kishore.gitbook.io/instant/

The basic usage for converting a DateTime to a timezone is very simple:

//Assumes Instant is in your pubspecimport 'package:instant/instant.dart';//Super Simple!DateTime myDT = DateTime.now(); //Current DateTimeDateTime EastCoast = dateTimeToZone(zone: "EST", datetime: myDT); //DateTime in EST zonereturn EastCoast;

This works with one line of code and minimal hassle.

Here is my solution for EST time zone but you can change it to any other

import 'package:timezone/data/latest.dart' as tz;import 'package:timezone/timezone.dart' as tz;extension DateTimeExtension on DateTime {  static int _estToUtcDifference;  int _getESTtoUTCDifference() {    if (_estToUtcDifference == null) {      tz.initializeTimeZones();      final locationNY = tz.getLocation('America/New_York');      tz.TZDateTime nowNY = tz.TZDateTime.now(locationNY);      _estToUtcDifference = nowNY.timeZoneOffset.inHours;    }    return _estToUtcDifference;  }  DateTime toESTzone() {    DateTime result = this.toUtc(); // local time to UTC    result = result.add(Duration(hours: _getESTtoUTCDifference())); // convert UTC to EST    return result;  }  DateTime fromESTzone() {    DateTime result = this.subtract(Duration(hours: _getESTtoUTCDifference())); // convert EST to UTC    String dateTimeAsIso8601String = result.toIso8601String();    dateTimeAsIso8601String += dateTimeAsIso8601String.characters.last.equalsIgnoreCase('Z') ? '' : 'Z';    result = DateTime.parse(dateTimeAsIso8601String); // make isUtc to be true    result = result.toLocal(); // convert UTC to local time    return result;  }}