how to format date YYYYMMDDmmhhssuuu

Question

I have a 'timestamp' value 20200513134950000 and the format should be YYYYMMDDmmhhssuuu. I can not wrap my head around how to properly format it. I have tried date-fns library and native Date format, but with no luck. Any ideas?

Euh, don't you have the correct format already? 2020-05-13 13:49:50.000 ? Or what exactly is the problem? Turning that number back into a Date object? — Shilly, Jun 30 '20 at 07:48
Does this answer your question? [How to format a JavaScript date](https://stackoverflow.com/questions/3552461/how-to-format-a-javascript-date) — Paddy, Jun 30 '20 at 08:55

score 1 · Answer 1 · answered Jun 30 '20 at 08:18

You can extract all the relevant parts from the number with a simple regexp or even by counting numbers. Then the only caveat is that months are zero-based, but apart from that, you can just use the standard Date() constructor.

const timestamp = 20200513134950000;

const UTC_mask = /(\d{4})(\d{2})(\d{2})(\d{2})(\d{2})(\d{2})(\d{3})/;

const [
  year,
  month,
  day,
  hour,
  min,
  sec,
  ms
] = timestamp.toString().match( UTC_mask ).slice( 1 );
      
const datetime = new Date( year, parseInt( month, 10 ) - 1, day, hour, min, sec, ms );

console.log( datetime );

The month can be just `month - 1`, the `-` operator coerces the string to number for you. ;-) — RobG, Jun 30 '20 at 08:46

score 1 · Answer 2 · answered Jun 30 '20 at 08:51

1

Without any library you can just get the parts and pass them to the Date constructor:

let ts = '20200513134950000';
let [c,y,m,d,H,M,S] = ts.match(/\d\d/g);
console.log(new Date(c+y,--m,d,H,M,S).toString());

answered Jun 30 '20 at 08:51

RobG

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score 0 · Accepted Answer · answered Jun 30 '20 at 08:06

You can try using DayJS. Its a lightweight library and allows you to specify custom parse format for parsing the dates.

const dayjs = require('dayjs');
var customParseFormat = require('dayjs/plugin/customParseFormat')
dayjs.extend(customParseFormat)
console.log(dayjs('20200513134950000', 'YYYYMMDDmmhhssuuu'))

how to format date YYYYMMDDmmhhssuuu

3 Answers3