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How can I get the timestamp in javascript from a string including the timezone db name

I got the following string: "2022/05/01 03:10:00" and I need to create a Date object forcing it to use Chile's UTC offset.
The problem is that because of Daylight saving time (DST) the offset changes twice a year.
How can get that Date object, for example, using the "America/Santiago" TZ db name?
Something like:
new Date("2022/05/01 03:10:00" + getUtcOffset("America/Santiago")).
function getUtcOffset(tzDbName) {
..
}
Returns -3 or -4, depending the time in the year.
EDIT:
I ended using a nice trick for determining if DST was on or off.
reference
const dst = hasDST(new Date(strDate));
function hasDST(date = new Date()) {
const january = new Date(date.getFullYear(), 0, 1).getTimezoneOffset();
const july = new Date(date.getFullYear(), 6, 1).getTimezoneOffset();
return Math.max(january, july) !== date.getTimezoneOffset();
}
Then I could create the date with the correct timezone depending on that variable.
if (dst) {
let d = new Date(strDate + " GMT-0300");
return d;
} else {
let d = new Date(strDate + " GMT-0400");
return d;
}
Thanks everyone!
EDIT2:
I finally found a very nice library that does exactly what I was looking for:
https://date-fns.org/v2.28.0/docs/Time-Zones#date-fns-tz
const { zonedTimeToUtc, utcToZonedTime, format } = require('date-fns-tz')
const utcDate = zonedTimeToUtc('2022-05-05 18:05', 'America/Santiago')

This has been discussed before here.
Haven't tested it, but it appears that the simplest solution is:
// Example for Indian time
let indianTime = new Date().toLocaleTimeString("en-US",
{timeZone:'Asia/Kolkata',timestyle:'full',hourCycle:'h24'})
console.log(indianTime)
You can check the link for more complex answers and libraries
Generals notes
To get the time zone name use:
console.log(Intl.DateTimeFormat().resolvedOptions().timeZone)
To get the difference from UTC (in minutes) use:
var offset = new Date().getTimezoneOffset();
console.log(offset);
// if offset equals -60 then the time zone offset is UTC+01

Material2 Datepicker - Convert date to timestamp without time [duplicate]

Can I convert iso date to milliseconds?
for example I want to convert this iso
2012-02-10T13:19:11+0000
to milliseconds.
Because I want to compare current date from the created date. And created date is an iso date.

Try this
var date = new Date("11/21/1987 16:00:00"); // some mock date
var milliseconds = date.getTime();
// This will return you the number of milliseconds
// elapsed from January 1, 1970
// if your date is less than that date, the value will be negative
console.log(milliseconds);
EDIT
You've provided an ISO date. It is also accepted by the constructor of the Date object
var myDate = new Date("2012-02-10T13:19:11+0000");
var result = myDate.getTime();
console.log(result);
Edit
The best I've found is to get rid of the offset manually.
var myDate = new Date("2012-02-10T13:19:11+0000");
var offset = myDate.getTimezoneOffset() * 60 * 1000;
var withOffset = myDate.getTime();
var withoutOffset = withOffset - offset;
console.log(withOffset);
console.log(withoutOffset);
Seems working. As far as problems with converting ISO string into the Date object you may refer to the links provided.
EDIT
Fixed the bug with incorrect conversion to milliseconds according to Prasad19sara's comment.

A shorthand of the previous solutions is
var myDate = +new Date("2012-02-10T13:19:11+0000");
It does an on the fly type conversion and directly outputs date in millisecond format.
Another way is also using parse method of Date util which only outputs EPOCH time in milliseconds.
var myDate = Date.parse("2012-02-10T13:19:11+0000");

Another option as of 2017 is to use Date.parse(). MDN's documentation points out, however, that it is unreliable prior to ES5.
var date = new Date(); // today's date and time in ISO format
var myDate = Date.parse(date);
See the fiddle for more details.

Yes, you can do this in a single line
let ms = Date.parse('2019-05-15 07:11:10.673Z');
console.log(ms);//1557904270673

Another possible solution is to compare current date with January 1, 1970, you can get January 1, 1970 by new Date(0);
var date = new Date();
var myDate= date - new Date(0);

Another solution could be to use Number object parser like this:
let result = Number(new Date("2012-02-10T13:19:11+0000"));
let resultWithGetTime = (new Date("2012-02-10T13:19:11+0000")).getTime();
console.log(result);
console.log(resultWithGetTime);
This converts to milliseconds just like getTime() on Date object

var date = new Date()
console.log(" Date in MS last three digit = "+ date.getMilliseconds())
console.log(" MS = "+ Date.now())
Using this we can get date in milliseconds

var date = new Date(date_string);
var milliseconds = date.getTime();
This worked for me!

if wants to convert UTC date to milliseconds
syntax : Date.UTC(year, month, ?day, ?hours, ?min, ?sec, ?milisec);
e.g :
date_in_mili = Date.UTC(2020, 07, 03, 03, 40, 40, 40);
console.log('miliseconds', date_in_mili);

In case if anyone wants to grab only the Time from a ISO Date, following will be helpful. I was searching for that and I couldn't find a question for it. So in case some one sees will be helpful.
let isoDate = '2020-09-28T15:27:15+05:30';
let result = isoDate.match(/\d\d:\d\d/);
console.log(result[0]);
The output will be the only the time from isoDate which is,
15:27

Javascript get UTC out of date and time variables

I have two variables in javascript like:
time: 02:00
date: 25-08-2017
and I'm wondering if I can put these into a Date() object and get the UTC date and time out of it in hours/minutes using getUTCDay(), getUTCHours() and getUTCMinutes() and place them back in the format I got them.
I can load moment.js for it but if I don't have to it would be nice if I can do it without.

Convert your strings to an ISO 8601 string and use it in the Date constructor. From there, you can get whatever data you need
let time = '02:00'
let date = '25-08-2017'
let iso8601Date = date.split('-').reverse().join('-')
let dt = new Date(`${iso8601Date}T${time}`) // will be interpreted as local time
const digitFormatter = new Intl.NumberFormat(undefined, {minimumIntegerDigits: 2})
console.info('Parsed date:', dt)
console.info('UTC date in dd-mm-yyyy:',
`${digitFormatter.format(dt.getUTCDate())}-${(digitFormatter.format(dt.getUTCMonth() + 1))}-${dt.getUTCFullYear()}`
)
console.info('UTC time:', `${digitFormatter.format(dt.getUTCHours())}:${digitFormatter.format(dt.getUTCMinutes())}`)

Changing date format javascript

I'm pulling some data from two different APIs and I want to the objects later on.
However, I'm getting two different date formats: this format "1427457730" and this format "2015-04-10T09:12:22Z". How can I change the format of one of these so I have the same format to work with?
$.each(object, function(index) {
date = object[index].updated_at;
}

Here's one option:
var timestamp = 1427457730;
var date = new Date(timestamp * 1000); // wants milliseconds, not seconds
var dateString = date.toISOString().replace(/\.\d+Z/, 'Z'); // remove the ms
dateString will now be 2015-03-27T12:02:10Z.

Try moment.js
var timestamp = 1427457730;
var date = '2015-04-10T09:12:22Z';
var m1 = moment(timestamp);
var m2 = moment(date);
console.log(m1);
console.log(m2);
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.11.1/moment.min.js"></script>
You can use .format() method in moment to parse the date to whatever format you want, just like:
m2.format('YYYY MMM DD ddd HH:mm:ss') // 2015 Apr 10 Fri 17:12:22
Check out the docs for more format tokens.

What you probably want in javascript, are date objects.
The first string is seconds since epoch, javascript needs milliseconds, so multiply it by 1000;
The second string is a valid ISO date, so if the string contains a hyphen just pass it into new Date.
var date = returned_date.indexOf('-') !== -1 ? returned_date : returned_date * 1000;
var date_object = new Date(date);
Making both types into date objects, you could even turn that into a handy function
function format_date(date) {
return new Date(date.indexOf('-') !== -1 ? date : date * 1000);
}
FIDDLE

Take a look at http://momentjs.com/. It is THE date/time formatting library for JavaScript - very simple to use, extremely flexible.

from unix timestamp to datetime

I have something like /Date(1370001284000+0200)/ as timestamp. I guess it is a unix date, isn't it? How can I convert this to a date like this: 31.05.2013 13:54:44
I tried THIS converter for 1370001284 and it gives the right date. So it is in seconds.
But I still get the wrong date for:
var substring = unix_timestamp.replace("/Date(", "");
substring = substring.replace("000+0200)/", "");
var date = new Date();
date.setSeconds(substring);
return date;

Note my use of t.format comes from using Moment.js, it is not part of JavaScript's standard Date prototype.
A Unix timestamp is the number of seconds since 1970-01-01 00:00:00 UTC.
The presence of the +0200 means the numeric string is not a Unix timestamp as it contains timezone adjustment information. You need to handle that separately.
If your timestamp string is in milliseconds, then you can use the milliseconds constructor and Moment.js to format the date into a string:
var t = new Date( 1370001284000 );
var formatted = moment(t).format("dd.mm.yyyy hh:MM:ss");
If your timestamp string is in seconds, then use setSeconds:
var t = new Date();
t.setSeconds( 1370001284 );
var formatted = moment(t).format("dd.mm.yyyy hh:MM:ss");

Looks like you might want the ISO format so that you can retain the timezone.
var dateTime = new Date(1370001284000);
dateTime.toISOString(); // Returns "2013-05-31T11:54:44.000Z"
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString

Without moment.js:
var time_to_show = 1509968436; // unix timestamp in seconds
var t = new Date(time_to_show * 1000);
var formatted = ('0' + t.getHours()).slice(-2) + ':' + ('0' + t.getMinutes()).slice(-2);
document.write(formatted);

The /Date(ms + timezone)/ is a ASP.NET syntax for JSON dates. You might want to use a library like momentjs for parsing such dates. It would come in handy if you need to manipulate or print the dates any time later.

If using react:
import Moment from 'react-moment';
Moment.globalFormat = 'D MMM YYYY';
then:
<td><Moment unix>{1370001284}</Moment></td>

Import moment js:
var fulldate = new Date(1370001284000);
var converted_date = moment(fulldate).format(");

if you're using React I found 'react-moment' library more easy to handle for Front-End related tasks, just import <Moment> component and add unix prop:
import Moment from 'react-moment'
// get date variable
const {date} = this.props
<Moment unix>{date}</Moment>

I would like to add that Using the library momentjs in javascript you can have the whole data information in an object with:
const today = moment(1557697070824.94).toObject();
You should obtain an object with this properties:
today: {
date: 15,
hours: 2,
milliseconds: 207,
minutes: 31,
months: 4
seconds: 22,
years: 2019
}
It is very useful when you have to calculate dates.

for people as dumb as myself, my date was in linux epoch
but it was a string instead of an integer, and that's why i was getting
RangeError: Date value out of bounds
so if you are getting the epoch from an api, parseInt it first
var dateTime = new Date(parseInt(1370001284000));
dateTime.toISOString();