JAVASCRIPT

javascript set date to timezone

var d = new Date("2020-04-13T00:00:00.000+08:00"); /* midnight in China on April 13th */
d.toLocaleString('en-US', { timeZone: 'America/New_York' });
//=> "4/12/2020, 12:00:00 PM"
// (midnight in China on April 13th is noon in New York on April 12th)

get timezone javascript

const timezone = Intl.DateTimeFormat().resolvedOptions().timeZone;
console.log(timezone);

get current time in different timezone javascript

// current datetime string in America/Chicago timezone
let chicago_datetime_str = new Date().toLocaleString("en-US", { timeZone: "America/Chicago" });

// create new Date object
let date_chicago = new Date(chicago_datetime_str);

get timezone name from date javascript

Intl.DateTimeFormat().resolvedOptions().timeZone

timezone offset to timezone in javascript

getGMT() {
    let gmtFigure = new Date().getTimezoneOffset() / -60;
    let gmtSign = gmtFigure >= 0 ? '+' : '-';
    let gmtlength = this.digits_count(gmtFigure);
    let gmt = 'GMT';
    if (gmtlength == 1) {
      gmt += gmtSign + '0' + Math.abs(gmtFigure);
    } else if (gmtlength > 1) {
      gmt += gmtSign + Math.abs(gmtFigure);
    }
    return gmt;
  }


digits_count(n) {
    var count = 0;
    n = Math.abs(n);
    if (n >= 1) ++count;
    while (n / 10 >= 1) {
      n /= 10;
      ++count;
    }
    return count;
  }

javascript parse date in current timezone

/*  @param {string} s - an ISO 8001 format date and time string
**                      with all components, e.g. 2015-11-24T19:40:00
**  @returns {Date} - Date instance from parsing the string. May be NaN.
*/
function parseISOLocal(s) {
  var b = s.split(/D/);
  return new Date(b[0], b[1]-1, b[2], b[3], b[4], b[5]);
}

document.write(parseISOLocal('2015-11-24T19:40:00'));

javascript date timezone

// this example takes 2 seconds to run
const start = Date.now();

console.log('starting timer...');
// expected output: starting timer...

setTimeout(() => {
  const millis = Date.now() - start;

  console.log(`seconds elapsed = ${Math.floor(millis/1000)}`);
  // expected output : seconds elapsed = 2
}, 2000);

timezone using javascript

' check time zone
DateDiff("s", "01/01/1970 00:00:00", Now())