Question

consider am having the string date and time.
say

var selfwDepDate    = document.forms[0].fwDepartureDate.value;
var selfwDepTime    = document.forms[0].fwDepartureTime.value;

and having time zone as

var orgTimeZone = document.getElementById('orginTimeZone').value;
var descTimeZone = document.getElementById('descTimeZone').value;

can any one how to convert the String date to GMT date..
value of orgTimeZone = Asia/Dubai
value of descTimeZone = America/New_York

Answer 1

I think you can use timezone-js.

Create a timezoneJS.Date the same way as a normal JavaScript Date,
but append a timezone parameter on the end:

var dt = new timezoneJS.Date('10/31/2008',
  'America/New_York');
var dt = new timezoneJS.Date(2008, 9, 31, 11, 45,
  'America/Los_Angeles');

OR

you can approach like this:-

var now = new Date();

var utc = new Date(Date.UTC(
    now.getFullYear(),
    now.getMonth(),
    now.getDate(),
    now.getHours(),
    now.getMinutes()
));

Now for different timezone you need to add or subtract the time by which they differ from GMT.
Note :-Date.UTC() returns the number of milliseconds since the epoch, UTC.