mirror of
				https://github.com/therootcompany/tz.js
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	docs!: toUTC* to fromTimeZone, toOffsetISOString
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								README.md
									
									
									
									
									
								
							@ -15,48 +15,26 @@ TZ.toLocalISOString(new Date()); // "2021-11-07T03:15:59.000-0500"
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TZ.timeZone(); // "America/New_York"
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```
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> What UTC time will it be when it's 3:15am in New York?
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```js
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// Relative New York time to Absolute UTC Time
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TZ.toUTCISOString("2021-11-07 03:15:59.000", "America/New_York");
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// What will the ISO datetime string be
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// when it's 3:15am in New York?
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//
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// (Relative New York time to Absolute UTC Time)
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TZ.toOffsetISOString("2021-11-07 03:15:59.000", "America/New_York");
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// "2021-11-07T03:15:59.000-0500"
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```
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```js
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var tzDate = TZ.toUTC("2021-11-07 03:15:59.000", "America/New_York");
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// {
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//   year: 2021, month: 10, day: 7,
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//   hour: 3, minute: 15, second: 59, millisecond: 0,
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//   offset: -300, timeZoneName: "Eastern Standard Time"
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// }
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// What time will it be in New York
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// when it's 7:15am UTC?
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//
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// (Absolute UTC time to Relative New York time)
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tzDate.toISOString();
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// "2021-11-07T03:15:59.000-0500"
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// (same as "2021-11-07T08:15:59.000Z")
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```
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> What time will it be in New York when it's 7:15am UTC?
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```js
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// Absolute UTC time to Relative New York time
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TZ.toTimeZoneISOString("2021-03-14T07:15:59.000Z", "America/New_York");
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// "2021-03-14T03:15:59.000-0400"
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```
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```js
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var utcDate = TZ.toTimeZone("2021-03-14T07:15:59.000Z", "America/New_York");
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// {
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//   year: 2021, month: 2, day: 14,
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//   hour: 3, minute: 15, second: 59, millisecond: 0,
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//   offset: -240, timeZoneName: "Eastern Daylight Time"
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// }
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utcDate.toISOString();
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// "2021-03-14T03:15:59.000-0400"
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// (same as "2021-11-07T07:15:59.000Z")
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```
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# Features
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- [x] Translate a UTC time to a Time Zone
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@ -108,8 +86,8 @@ https://www.youtube.com/playlist?list=PLxki0D-ilnqa6horOJ2G18WMZlJeQFlAt
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- `toLocalISOString(dateOrNull)`
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- `toTimeZone(utcDate, timeZone)`
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- `toTimeZoneISOString(isoString, timeZone)`
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- `toUTC(dtString, timeZone)`
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- `toUTCISOString(dtString, timeZone)`
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- `fromTimeZone(dtString, timeZone)`
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- `toOffsetISOString(dtString, timeZone)`
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## `toTimeZone(utcDate, timeZone)`
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@ -121,20 +99,33 @@ Use ISO timestamps representing the absolute UTC time (with or without offset):
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"2021-11-07T08:15:59.000Z"
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```
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Convert directly to an ISO String:
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```js
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var utcDate = TZ.toTimeZone("2021-03-14T07:15:59.000Z", "America/New_York");
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// {
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//   year: 2021, month: 2, day: 14,
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//   hour: 3, minute: 15, second: 59, millisecond: 0,
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//   offset: -240, timeZoneName: "Eastern Daylight Time"
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// }
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utcDate.toISOString();
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// "2021-03-14T03:15:59.000-0400"
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// (same as "2021-11-07T07:15:59.000Z")
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```
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### Convert directly to an ISO String:
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```js
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TZ.toTimeZoneISOString("2021-11-07T08:15:59.000Z", "America/New_York");
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// "2021-11-07T03:15:59.000-0500"
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```
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Or use our bespoke (custom) date object:
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### Or use our bespoke (custom) date object:
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```js
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var tzDate = TZ.toTimeZone("2021-11-07T08:15:59.000Z", "America/New_York");
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```
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You can also use a date object with an absolute UTC time:
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### You can also use a date object with an absolute UTC time:
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```js
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var tzDate = TZ.toTimeZone(
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@ -148,14 +139,14 @@ console.log(tzDate.toISOString());
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// "2021-11-07T03:15:59.000-0500"
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```
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Our ISO Strings + Offsets work with JavaScript's native Date object!!
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### Our ISO Strings + Offsets work with JavaScript's native Date object!!
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```js
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new Date("2021-11-07T03:15:59.000-0500").toISOString());
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// "2021-11-07T08:15:59.000Z"
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```
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## `toUTC(dtString, timeZone)`
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## `fromTimeZone(dtString, timeZone)`
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> Convert a Target Time Zone into UTC
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@ -165,24 +156,39 @@ Use ISO-like timestamps representing the _local_ time in the target time zone:
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"2021-11-0 03:15:59.000"
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```
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Convert directly to an offset ISO String:
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```js
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var tzDate = TZ.fromTimeZone("2021-11-07 03:15:59.000", "America/New_York");
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// {
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//   year: 2021, month: 10, day: 7,
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//   hour: 3, minute: 15, second: 59, millisecond: 0,
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//   offset: -300, timeZoneName: "Eastern Standard Time"
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// }
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tzDate.toISOString();
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// "2021-11-07T03:15:59.000-0500"
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// (same as "2021-11-07T08:15:59.000Z")
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```
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### Convert directly to an offset ISO String:
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```js
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TZ.toUTCISOString("2021-11-07 03:15:59.000", "America/New_York");
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TZ.toOffsetISOString("2021-11-07 03:15:59.000", "America/New_York");
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// "2021-11-07T03:15:59.000-0500"
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```
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Or our bespoke date object:
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### Or our bespoke date object:
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```js
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var utcDate = TZ.toUTC("2021-11-07 03:15:59.000", "America/New_York");
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var utcDate = TZ.fromTimeZone("2021-11-07 03:15:59.000", "America/New_York");
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```
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### Use a Date as a source time
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You can also use a date object as the source time, but the date's UTC time will be treated as **_relative to time
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zone_** rather than absolute (this is a workaround for JavaScript's lack of bi-directional timezone support).
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```js
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var utcDate = TZ.toUTC(
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var utcDate = TZ.fromTimeZone(
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  new Date("2021-11-07T03:15:59.000Z"),
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  "America/New_York"
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);
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@ -207,7 +213,7 @@ Q: What happens in March when 2am is skipped?
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- A: Although 2am is not a valid time, rather than throwing an error this library will resolve to 1am instead, which
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  is an hour early in real ("tick-tock" or "monotonic") time.
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  ```js
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  var utcDate = TZ.toUTC("2021-03-14 02:15:59.000", "America/New_York");
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  var utcDate = TZ.fromTimeZone("2021-03-14 02:15:59.000", "America/New_York");
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  utcDate.toISOString();
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  // "2021-03-14T02:15:59.000-0400"
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  // (same as "2021-03-14T01:15:59.000-0500")
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@ -218,7 +224,7 @@ Q: What happens in November when 1am happens twice?
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- A: Although both 1ams are distinguishable with ISO offset times, only the first can be resolved from a local time
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  with this library.
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  ```js
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  var utcDate = TZ.toUTC("2021-11-07 01:15:59.000", "America/New_York");
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  var utcDate = TZ.fromTimeZone("2021-11-07 01:15:59.000", "America/New_York");
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  utcDate.toISOString();
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  // "2021-11-07T01:15:59.000-0400", same as "2021-11-07T05:15:59.000Z"
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  // (an hour before the 2nd 1am at "2021-11-07T01:15:59.000-0500")
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										18
									
								
								index.html
									
									
									
									
									
								
							
							
						
						
									
										18
									
								
								index.html
									
									
									
									
									
								
							@ -99,8 +99,8 @@ String(((new Date()).getTimezoneOffset() % 60)).padStart(2, '0')</code></pre>
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    <hr />
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    <form class="js-tz2utc">
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      <h3>Relative TimeZone to Absolute UTC:</h3>
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      <pre><code>XTZ.toUTC("<span class="js-dtx-tz">YYYY-03-14 03:15:69.000</span>", "<span class="js-tzx-tz">UTC</span>")
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      <h3>TimeZone-Relative (Local) to Absolute (ISO+Offset) String:</h3>
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      <pre><code>XTZ.fromTimeZone("<span class="js-dtx-tz">YYYY-03-14 03:15:69.000</span>", "<span class="js-tzx-tz">UTC</span>")
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   .toISOString()
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// <span class="js-myx-dt-tz"></span></code></pre>
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      <label>
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@ -130,14 +130,14 @@ String(((new Date()).getTimezoneOffset() % 60)).padStart(2, '0')</code></pre>
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      </label>
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      <br />
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      <br />
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      <button type="submit">Convert to UTC!</button>
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      <button type="submit">Convert to ISO+Offset!</button>
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      <br />
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    </form>
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    <hr />
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    <form class="js-utc2tz">
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      <h3>Absolute UTC to Relative TimeZone</h3>
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      <h3>Absolute (UTC) to TimeZone-Relative (ISO+Offset) String:</h3>
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      <pre><code>XTZ.toTimeZone("<span class="js-dtx-utc">YYYY-03-14 03:15:69.000</span>", "<span class="js-tzx-utc">UTC</span>")
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   .toISOString()
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// <span class="js-myx-dt-utc"></span></code></pre>
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@ -201,17 +201,17 @@ Asia/Kolkata        +0530 (No DST) (30-min)</pre
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      }
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      function translate(dt, tz, tz2) {
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        var utc = new Date(XTZ.toUTC(dt, tz).toISOString());
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        var utc = new Date(XTZ.fromTimeZone(dt, tz).toISOString());
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        if (!tz2) {
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          return utc;
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        }
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        return XTZ.toTimeZone(utc, tz2);
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      }
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      function toUTC() {
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      function fromTimeZone() {
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        var curDt = $(".js-dt-tz").value;
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        var curTz = $(".js-tz-tz").value;
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        $(".js-my-dt-tz").value = XTZ.toUTC(curDt, curTz).toISOString();
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        $(".js-my-dt-tz").value = XTZ.fromTimeZone(curDt, curTz).toISOString();
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        $(".js-dtx-tz").innerText = curDt;
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        $(".js-tzx-tz").innerText = curTz;
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@ -265,10 +265,10 @@ Asia/Kolkata        +0530 (No DST) (30-min)</pre
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      $("form.js-tz2utc").addEventListener("submit", function (ev) {
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        ev.preventDefault();
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        ev.stopPropagation();
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        toUTC();
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        fromTimeZone();
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      });
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      toUTC();
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      fromTimeZone();
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      toTZ();
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      xTZ();
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    </script>
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										49
									
								
								xtz.js
									
									
									
									
									
								
							
							
						
						
									
										49
									
								
								xtz.js
									
									
									
									
									
								
							@ -1,6 +1,4 @@
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var XTZ;
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(function () {
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(function (exports) {
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  "use strict";
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  function toTimeZone(date, timeZone) {
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@ -62,15 +60,16 @@ var XTZ;
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  function toTimeZoneISOString(date, timeZone) {
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    var whole = toTimeZone(date, timeZone);
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    return toOffsetISOString(whole);
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    return formatAsOffsetISOString(whole);
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		||||
  }
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  function _toOffsetISOString() {
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    return toOffsetISOString(this);
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    /* jshint validthis: true */
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    return formatAsOffsetISOString(this);
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		||||
  }
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  function getOffset(utcDate, tzD2) {
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		||||
    var tzDate = new Date(toOffsetISOString(tzD2));
 | 
			
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    var tzDate = new Date(formatAsOffsetISOString(tzD2));
 | 
			
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    var diff = Math.round((tzDate.valueOf() - utcDate.valueOf()) / (60 * 1000));
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    return diff;
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  }
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@ -98,10 +97,21 @@ var XTZ;
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    }
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    // +0500, -0730
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    return offset + p2(h) + p2(m);
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    return (
 | 
			
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      offset + h.toString().padStart(2, "0") + m.toString().padStart(2, "0")
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		||||
    );
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		||||
  }
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		||||
 | 
			
		||||
  function toOffsetISOString(d) {
 | 
			
		||||
  function toOffsetISOString(date, timeZone) {
 | 
			
		||||
    if ("offset" in date && "year" in date) {
 | 
			
		||||
      return formatAsOffsetISOString(date);
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    }
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    var whole = fromTimeZone(date, timeZone);
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		||||
    return formatAsOffsetISOString(whole);
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		||||
  }
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		||||
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  function formatAsOffsetISOString(d) {
 | 
			
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    var offset = formatOffset(d.offset);
 | 
			
		||||
    return (
 | 
			
		||||
      `${d.year}-${p2(d.month + 1)}-${p2(d.day)}` +
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@ -111,7 +121,7 @@ var XTZ;
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		||||
    );
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		||||
  }
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 | 
			
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  function toUTC(dt, tz) {
 | 
			
		||||
  function fromTimeZone(dt, tz) {
 | 
			
		||||
    if ("string" === typeof dt) {
 | 
			
		||||
      // Either of these formats should work:
 | 
			
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      // 2021-03-14 01:15:59
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@ -148,11 +158,6 @@ var XTZ;
 | 
			
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    return tzD3;
 | 
			
		||||
  }
 | 
			
		||||
 | 
			
		||||
  function toUTCISOString(date, timeZone) {
 | 
			
		||||
    var whole = toUTC(date, timeZone);
 | 
			
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    return toOffsetISOString(whole);
 | 
			
		||||
  }
 | 
			
		||||
 | 
			
		||||
  function toLocalISOString(dateOrStr) {
 | 
			
		||||
    var d;
 | 
			
		||||
    if (dateOrStr) {
 | 
			
		||||
@ -174,15 +179,17 @@ var XTZ;
 | 
			
		||||
    return `${YYYY}-${MM}-${DD}T${hh}:${mm}:${ss}.${sss}${offset}`;
 | 
			
		||||
  }
 | 
			
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 | 
			
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  XTZ = {
 | 
			
		||||
  exports.XTZ = {
 | 
			
		||||
    // bespoke date =>
 | 
			
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    // 2021-11-07T3:15:59-0500
 | 
			
		||||
    // (todo?)
 | 
			
		||||
    // xtzToISOString: formatAsOffsetISOString,
 | 
			
		||||
    // (deprecated)
 | 
			
		||||
    toOffsetISOString: toOffsetISOString,
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		||||
 | 
			
		||||
    // -240 => -0400
 | 
			
		||||
    formatOffset: formatOffset,
 | 
			
		||||
 | 
			
		||||
    // new Date() => "2021-11-07T03:15:59-0500"
 | 
			
		||||
    toLocalISOString: toLocalISOString,
 | 
			
		||||
 | 
			
		||||
    // [ "2021-11-07T08:15:59Z", "America/New_York" ]
 | 
			
		||||
@ -192,11 +199,13 @@ var XTZ;
 | 
			
		||||
 | 
			
		||||
    // [ "2021-11-07 03:15:59", "America/New_York" ]
 | 
			
		||||
    // => "2021-11-07T03:15:59-0500" // 2021-11-07T08:15:59Z
 | 
			
		||||
    toUTC: toUTC,
 | 
			
		||||
    toUTCISOString: toUTCISOString,
 | 
			
		||||
    toUTC: fromTimeZone,
 | 
			
		||||
    fromTimeZone: fromTimeZone,
 | 
			
		||||
    // deprecated
 | 
			
		||||
    toUTCISOString: toOffsetISOString,
 | 
			
		||||
  };
 | 
			
		||||
 | 
			
		||||
  if ("undefined" != typeof module && module.exports) {
 | 
			
		||||
    module.exports = XTZ;
 | 
			
		||||
    module.exports = exports.XTZ;
 | 
			
		||||
  }
 | 
			
		||||
})();
 | 
			
		||||
})(("undefined" === typeof module && window) || exports);
 | 
			
		||||
 | 
			
		||||
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