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