title: javascript dates and timezones in angular
body: <p>I am going absolutely insane trying to work out how to get two dates, from two different time zones to show the same times regardless of where you are.</p>
  
  <p>ie: If I have a time in Melbourne (GMT +1000) at 7am, and I have another in Perth (GMT +0800) at 7am I would like them both to show in a bootstrap timepicker as 07:00 on the same page.</p>
  
  <p>If I am in Melbourne the actual time in Perth is 2 hours behind. There are many different time zones in Australia with daylight savings thrown into the mix.</p>
  
  <p>I understand that JS dates are localised to the region of where the computer is set, so I am assuming that the computer in question is correct.</p>
  
  <p>I have created a filter using momentjs and moment-timezones but I just cannot get it to show the correct results.</p>
  
  <p>An example input is: "2017-07-28T23:00:00.000Z" - or Sat Jul 29 2017 07:00:00 GMT+0800 (AWST).</p>
  
  <p>I have found that momentjs does a great job of converting times into strings, but how do I successfully convert that into a date object?</p>
  
  <p>Here is my code so far:</p>
  
  <pre><code>  (function () {
    'use strict';
  
    angular
      .module('bookings')
      .filter('timezone', timezone);
  
    timezone.$inject = [];
  
    function timezone() {
  
      function isCurrentTimeZone(code){
        var currentTimeCode = new Date().toString().split('(')[1].replace(')','');
  
        if (code.indexOf(currentTimeCode) &gt;= 0) {
          return true;
        }
  
        return false;
      }
  
      function getLocalAustralianTimeZone() {
  
        var currentTimeCode = new Date().toString().split('(')[1].replace(')','');
  
        let timezones = [
          { state: 'NSW', tz: 'Australia/Sydney', code: 'AEST AEDT' },
          { state: 'QLD', tz: 'Australia/Brisbane', code: 'AEST AEDT' },
          { state: 'SA', tz: 'Australia/Adelaide', code: 'ACST ACDT' },
          { state: 'TAS', tz: 'Australia/Hobart', code: 'AEST AEDT' },
          { state: 'NT', tz: 'Australia/Darwin', code: 'ACST ACDT' },
          { state: 'VIC', tz: 'Australia/Melbourne', code: 'AEST AEDT' },
          { state: 'WA', tz: 'Australia/Perth', code: 'AWST AWDT' },
          { state: 'ACT', tz: 'Australia/Sydney', code: 'AEST AEDT' }
        ];
  
        let selectedTz = _.find(timezones, function (o) {
          return o.code.indexOf(currentTimeCode) &gt;= 0;
        });
        return selectedTz;
      }
  
      function getAustralianTimeZone(state) {
        let timezones = [
          { state: 'NSW', tz: 'Australia/Sydney', code: 'AEST AEDT' },
          { state: 'QLD', tz: 'Australia/Brisbane', code: 'AEST AEDT' },
          { state: 'SA', tz: 'Australia/Adelaide', code: 'ACST ACDT' },
          { state: 'TAS', tz: 'Australia/Hobart', code: 'AEST AEDT' },
          { state: 'NT', tz: 'Australia/Darwin', code: 'ACST ACDT' },
          { state: 'VIC', tz: 'Australia/Melbourne', code: 'AEST AEDT' },
          { state: 'WA', tz: 'Australia/Perth', code: 'AWST AWDT' },
          { state: 'ACT', tz: 'Australia/Sydney', code: 'AEST AEDT' }
        ];
  
        let selectedTz = _.find(timezones, function (o) {
          return o.state === state;
        });
        return selectedTz;
      }
  
      function createDateAsUTC(date) {
        return new Date(Date.UTC(date.getFullYear(), date.getMonth(), date.getDate(), date.getHours(), date.getMinutes(), date.getSeconds()));
      }
  
      function convertDateToUTC(date) {
        return new Date(date.getUTCFullYear(), date.getUTCMonth(), date.getUTCDate(), date.getUTCHours(), date.getUTCMinutes(), date.getUTCSeconds());
      }
  
      return function (val, state) {
        moment.tz.add('Australia/Sydney|AEST AEDT|-a0 -b0|0101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101|-293lX xcX 10jd0 yL0 1cN0 1cL0 1fB0 19X0 17c10 LA0 1C00 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Rc0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 14o0 1o00 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 U00 1qM0 WM0 1tA0 WM0 1tA0 U00 1tA0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Rc0 1zc0 Oo0 1zc0 Oo0 1zc0 11A0 1o00 11A0 1o00 11A0 1o00 11A0 1qM0 WM0 11A0 1o00 1qM0 11A0 1o00 11A0 1o00 11A0 1qM0 WM0 1qM0 11A0 1o00 WM0 1qM0 14o0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0|40e5');
        moment.tz.add('Australia/Adelaide|ACST ACDT|-9u -au|0101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101|-293lt xcX 10jd0 yL0 1cN0 1cL0 1fB0 19X0 17c10 LA0 1C00 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Rc0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Rc0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 U00 1qM0 WM0 1tA0 WM0 1tA0 U00 1tA0 U00 1tA0 Oo0 1zc0 WM0 1qM0 Rc0 1zc0 U00 1tA0 WM0 1qM0 11A0 1o00 11A0 1o00 11A0 1o00 11A0 1qM0 WM0 1qM0 WM0 1qM0 11A0 1o00 11A0 1o00 11A0 1qM0 WM0 1qM0 11A0 1o00 WM0 1qM0 14o0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0|11e5');
        moment.tz.add('Australia/Brisbane|AEST AEDT|-a0 -b0|01010101010101010|-293lX xcX 10jd0 yL0 1cN0 1cL0 1fB0 19X0 17c10 LA0 H1A0 Oo0 1zc0 Oo0 1zc0 Oo0|20e5');
        moment.tz.add('Australia/Broken_Hill|ACST ACDT|-9u -au|0101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101|-293lt xcX 10jd0 yL0 1cN0 1cL0 1fB0 19X0 17c10 LA0 1C00 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Rc0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 14o0 1o00 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 U00 1qM0 WM0 1tA0 WM0 1tA0 U00 1tA0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Rc0 1zc0 Oo0 1zc0 Oo0 1zc0 11A0 1o00 11A0 1o00 11A0 1o00 11A0 1qM0 WM0 1qM0 WM0 1qM0 11A0 1o00 11A0 1o00 11A0 1qM0 WM0 1qM0 11A0 1o00 WM0 1qM0 14o0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0|18e3');
        moment.tz.add('Australia/Currie|AEST AEDT|-a0 -b0|0101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101|-29E80 19X0 10jd0 yL0 1cN0 1cL0 1fB0 19X0 17c10 LA0 1C00 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Rc0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 11A0 1qM0 WM0 1qM0 Oo0 1zc0 Oo0 1zc0 Oo0 1wo0 WM0 1tA0 WM0 1tA0 U00 1tA0 U00 1tA0 11A0 1fA0 1a00 1fA0 1a00 1fA0 1a00 1fA0 1a00 1fA0 1cM0 1fA0 1a00 1fA0 1a00 1fA0 1a00 1fA0 1a00 11A0 1o00 1io0 1a00 1fA0 1a00 1fA0 1a00 1fA0 1a00 1fA0 1cM0 1cM0 1a00 1io0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0|746');
        moment.tz.add('Australia/Darwin|ACST ACDT|-9u -au|010101010|-293lt xcX 10jd0 yL0 1cN0 1cL0 1fB0 19X0|12e4');
        moment.tz.add('Australia/Eucla|+0845 +0945|-8J -9J|0101010101010101010|-293kI xcX 10jd0 yL0 1cN0 1cL0 1gSp0 Oo0 l5A0 Oo0 iJA0 G00 zU00 IM0 1qM0 11A0 1o00 11A0|368');
        moment.tz.add('Australia/Hobart|AEST AEDT|-a0 -b0|010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101|-29E80 19X0 10jd0 yL0 1cN0 1cL0 1fB0 19X0 VfB0 1cM0 1o00 Rc0 1wo0 Rc0 1wo0 U00 1wo0 LA0 1C00 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Rc0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 11A0 1qM0 WM0 1qM0 Oo0 1zc0 Oo0 1zc0 Oo0 1wo0 WM0 1tA0 WM0 1tA0 U00 1tA0 U00 1tA0 11A0 1fA0 1a00 1fA0 1a00 1fA0 1a00 1fA0 1a00 1fA0 1cM0 1fA0 1a00 1fA0 1a00 1fA0 1a00 1fA0 1a00 11A0 1o00 1io0 1a00 1fA0 1a00 1fA0 1a00 1fA0 1a00 1fA0 1cM0 1cM0 1a00 1io0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0|21e4');
        moment.tz.add('Australia/Lord_Howe|AEST +1030 +1130 +11|-a0 -au -bu -b0|0121212121313131313131313131313131313131313131313131313131313131313131313131313131313131313131313131313131313131313|raC0 1zdu Rb0 1zd0 On0 1zd0 On0 1zd0 On0 1zd0 TXu 1qMu WLu 1tAu WLu 1tAu TXu 1tAu Onu 1zcu Onu 1zcu Onu 1zcu Rbu 1zcu Onu 1zcu Onu 1zcu 11zu 1o0u 11zu 1o0u 11zu 1o0u 11zu 1qMu WLu 11Au 1nXu 1qMu 11zu 1o0u 11zu 1o0u 11zu 1qMu WLu 1qMu 11zu 1o0u WLu 1qMu 14nu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1fAu 1cLu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1fAu 1cLu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1cMu 1fzu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1fAu 1cLu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1cMu 1cLu 1fAu 1cLu 1cMu 1cLu 1cMu|347');
        moment.tz.add('Australia/Lindeman|AEST AEDT|-a0 -b0|010101010101010101010|-293lX xcX 10jd0 yL0 1cN0 1cL0 1fB0 19X0 17c10 LA0 H1A0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Rc0 1zc0 Oo0|10');
        moment.tz.add('Australia/Melbourne|AEST AEDT|-a0 -b0|0101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101|-293lX xcX 10jd0 yL0 1cN0 1cL0 1fB0 19X0 17c10 LA0 1C00 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Rc0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 Rc0 1zc0 Oo0 1zc0 Oo0 1zc0 Oo0 1zc0 U00 1qM0 WM0 1qM0 11A0 1tA0 U00 1tA0 U00 1tA0 Oo0 1zc0 Oo0 1zc0 Rc0 1zc0 Oo0 1zc0 WM0 1qM0 11A0 1o00 11A0 1o00 11A0 1o00 11A0 1qM0 WM0 11A0 1o00 1qM0 11A0 1o00 11A0 1o00 11A0 1qM0 WM0 1qM0 11A0 1o00 WM0 1qM0 14o0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1cM0 1fA0 1cM0 1cM0 1cM0 1cM0|39e5');
        moment.tz.add('Australia/Perth|AWST AWDT|-80 -90|0101010101010101010|-293jX xcX 10jd0 yL0 1cN0 1cL0 1gSp0 Oo0 l5A0 Oo0 iJA0 G00 zU00 IM0 1qM0 11A0 1o00 11A0|18e5');
  
        if (state !== "") {
          var timezone = getAustralianTimeZone(state);
          var currentZone = getLocalAustralianTimeZone();
          var isCurrent = isCurrentTimeZone(timezone.code);
  
  
          if (!isCurrent) {
  
            var date = new Date(Date.parse(val));
            date = new Date(date.getTime() - (60000 * moment(val).tz(timezone.tz)._offset));
            return date;
          }
  
          return new Date(Date.parse(val));
  
        }
  
        return new Date(val);
      };
    }
  }());
  </code></pre>