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get new Date() in other timezone in full text string format

I need to get Thailand timezone in this format: Thu Nov 10 2022 14:08:37 GMT+0800 (Malaysia Time). I have tried new Date().toLocaleString("en-US", {timeZone: "Asia/Bangkok"}) but didn't get the correct format I want, probably because of the .toLocaleString(). Is there a simple way to do it?

As deceze suggests, you can use Intl.DateTimeFormat with suitable options to get the values you want. Then you can use formatToParts to reorganise them as you wish, e.g. to replicate the format of Date.prototype.toString for any timezone, you can use:
// Return timestamp in same format as Date.prototype.toString
// in designated timezone (IANA representative location)
function toTimezone(tz, date = new Date()) {
// Get parts except timezone name
let opts = {
year: 'numeric',
month: 'short',
day: '2-digit',
weekday: 'short',
hour: '2-digit',
minute: '2-digit',
second: '2-digit',
timeZone: tz,
timeZoneName: 'shortOffset',
hour12: false
}
// To get full timezone name
let opts2 = {
hour: 'numeric',
timeZone: tz,
timeZoneName: 'long'
}
let toParts = opts => new Intl.DateTimeFormat('en', opts)
.formatToParts(date)
.reduce((acc, part) => {
acc[part.type] = part.value;
return acc;
}, Object.create(null));
let {year, month, day, weekday, hour, minute,
second, timeZoneName} = toParts(opts);
// Fix offset
let sign = /\+/.test(timeZoneName)? '+' : '-';
let [oH, oM] = timeZoneName.substr(4).split(':');
let offset = `GMT${sign}${oH.padStart(2, '0')}${oM || '00'}`;
// Get timezone name
timeZoneName = toParts(opts2).timeZoneName;
return `${weekday} ${month} ${day} ${year} ${hour}:${minute}:${second} ${offset} (${timeZoneName})`;
}
// Examples
['Australia/Adelaide',
'Asia/Bangkok',
'Asia/Kolkata',
'America/New_York',
'Pacific/Yap',
'Pacific/Pago_Pago'
].forEach(tz => console.log(toTimezone(tz)));
Support for some options like shortOffset may not be ubiquitous yet. A formatting library with timezone support is a simpler (and more reliable) option. :-)

You can configure the locale string formatter with a whole bunch of options:
console.log(new Date().toLocaleString('en-US', {
timeZone: 'Asia/Bangkok',
weekday: 'short',
year: 'numeric',
month: 'short',
day: 'numeric',
hour: 'numeric',
minute: 'numeric',
second: 'numeric',
timeZoneName: 'short',
hour12: false
}));
However, the exact format it will output will always be dependent on the locale used and the browser's understanding of how dates should be formatted for that locale. If you want more control over the exact formatting, you'll need to cobble it together yourself:
const date = new Date();
const time = date.toLocaleString('en-US', {
timeZone: 'Asia/Bangkok',
hour: 'numeric',
minute: 'numeric',
second: 'numeric',
timeZoneName: 'short',
hour12: false
});
const weekday = date.toLocaleString('en-US', {
timeZone: 'Asia/Bangkok',
weekday: 'short'
});
console.log(`${weekday} ${date.getFullYear()} ... ${time}`);
If that seems too complicated, use some 3rd party library like Luxon, which can simplify that a bit.

toLocaleString adding custom letters

In this code below I need to render time looking like this 3h15m. Now it's just 3:15. How can I add endings to hours and minutes? Thank you in advance.
<span className={s.data}>{new Date(ticket.segments[0].duration)
.toLocaleString('en', { hour: 'numeric',
minute: 'numeric' })}</span>

Like this
let [, hh, mm] = new Date(2020, 07, 12, 15, 30, 0)
.toLocaleString('en', {
hour: 'numeric',
minute: 'numeric'
}).match(/(\d{1,2})\:(\d{2})/)
console.log(`${hh}h${mm}m`)

Js Date - Unix Time Stamp wrong result

Hi I have generated a Unix Time Stamp with an online generator and I choose that Date:
01/12/2020 # 9:30pm (UTC)
Which gave me result: 1578864600
I want to display it now in my react app: (date is my result above)
const timestamp = new Date().setMilliseconds(date);
const formattedDate = new Intl.DateTimeFormat('pl-PL', {
year: 'numeric',
month: 'numeric',
day: 'numeric',
weekday: 'long',
hour: 'numeric',
minute: 'numeric',
}).format(timestamp);
But in my react app I am getting that wrong Date:
Tuesday, 14.01.2020, 17:07
Why it is calculating it wrong??

how to add only minutes in HH:MM format in javascript?

I am getting time HH:MM format using
dt.toLocaleTimeString('en-US', { hour: 'numeric', minute: 'numeric' })
I need to add only minutes?
I am getting one more error this is my date (2018-08-15T06:08:55.000Z) here, when I try to display time it displays different time '11:38' I need '06:08'..
console.log('data as ', obj);
var dat = obj.starttime;
let dt = new Date(dat);
console.log('time from database' , dt);
console.log('getMinutes():' + dt.toLocaleTimeString('en-US', { hour: 'numeric', minute: 'numeric' }) );
output of the console.log
data as { id: 4009,mid: 1,cid: 41,wid: 7138,oid: null,
status: null,options: null, starttime: '2018-08-15T06:08:55.000Z',
duration: null,ordertotal: 50,counter: null,closetime: null }
time from database 2018-08-15T06:08:55.000Z
getMinutes():11:38 AM
Here I am getting different time than required time...and I need to add only minutes to it.

You should add the timeZone option and to add minutes use Date.setMinutes():
var dat = '2018-08-15T06:08:55.000Z'; //obj.starttime;
let dt = new Date(dat);
console.log('getMinutes(): ' + dt.toLocaleTimeString('en-US', { timeZone: 'UTC', hour: 'numeric', minute: 'numeric' }) );
// to Add minutes:
dt.setMinutes(dt.getMinutes() + 10);
console.log('getMinutes(): ' + dt.toLocaleTimeString('en-US', { timeZone: 'UTC', hour: 'numeric', minute: 'numeric' }) );

date.toLocaleString(options) does not work javascript

I am quite new to JS and need some help.
I want to format date with the help of toLocaleString(). According to standards first argument 'locales' can be omitted. My code looks like:
let myDate = new Date(2014, 0, 30)
let options = {
year: '2-digit',
month: '2-digit',
day: '2-digit'
};
let formattedDate = myDate.toLocaleString(options);
console.log(formattedDate);

While you can skip the first argument, without supplying something for it in your case, you won't get the options argument to give you the results you want.
Here are a few versions of working code:
let date = new Date(2014, 0, 30);
let options = {
year: '2-digit',
month: '2-digit',
day: '2-digit'
};
console.log(date.toLocaleString('en-us', options));
console.log(date.toLocaleString(undefined, options));
console.log(date.toLocaleString(options));
options.timeZone = 'UTC';
options.timeZoneName = 'short';
console.log(date.toLocaleString('en-US', options));
// sometimes even the US needs 24-hour time
console.log(date.toLocaleString('en-US', { hour12: false }));

The first argument to toLocaleString is not optional, but you can pass undefined to it.
let date = new Date(2014, 0, 30)
let options = {
year: '2-digit',
month: '2-digit',
day: '2-digit'
};
let formattedDate = date.toLocaleString(undefined, options);
console.log(formattedDate);

You should use the options as second parameter:
let date = new Date(2014, 2, 2)
let options = {
year: '2-digit',
month: '2-digit',
day: '2-digit'
};
let formattedDate = date.toLocaleString(undefined, options);