Formatting

The format() method returns a string representing an esday object.

Usage

Method signatures

Formatting using a given format template

esday().format(formatTemplate: string): string

parameter	description
formatTemplate	template used for formatting the EsDay object

Adding new formatting tokens

esday.addTokenDefinitions(newTokens: TokenDefinitions)

Format of TokenDefinitions

type TokenDefinitions = Record<token, [regexDefaultMode, regexStrictMode, setterFn]>

parameter	type	description
token	string	token to be parsed (e.g. 'Q')
regexDefaultMode	RegExp	regex used for parsing in default mode
regexStrictMode	RegExp	regex used for parsing in strict mode
setterFn	function	function to add parsed value to result in 'this'

Signature of setterFn

(this: ParsedElements, input: string) => void

Parameters of setter

parameter	type	description
this	ParsedElements	object for results of parsing
input	string	parsed value

Format of ParsedElements

interface ParsedElements {
  year?: number
  month?: number
  day?: number
  hours?: number
  minutes?: number
  seconds?: number
  milliseconds?: number
  zoneOffset?: number
  unix?: number
}

Parsing tokens

Token	Example	Description
YY	1	Two-digit year
YYYY	2001	Four-digit year
M	1-12	Month, beginning at 1
MM	01-12	Month, 2-digits
D	1-31	Day of month
DD	01-31	Day of month, 2-digits
H	0-23	Hours
HH	00-23	Hours, 2-digits
m	0-59	Minutes
mm	00-59	Minutes, 2-digits
s	0-59	Seconds
ss	00-59	Seconds, 2-digits
SSS	000-999	Milliseconds, 3-digits
Z	+05:00:00	Offset from UTC

To use one of the supported tokens as test between the date elements, these characters must be escaped (i.e.wrapped in square brackets).
An example for a formatting string with escaped test is YYY-MM-DD [MM] HH [any other text] mm [m]b.

Examples

Formatting

import { esday } from 'esday'

esday('08-2023-14 21:43:12.123').format('MM-YYYY-DD HH:mm:ss.SSS')
// Returns '2023-08-14T21:43:12.123'

Adding new formatting tokens

This functionality is above all for plugin developers

const additionalTokens: TokenDefinitions = {
  PP: [/\d\d?/, /\d{2}/, function (input) {
    // in this example we don't use the parsed value ('input')
    this.milliseconds = 987
  }],
}
esday.addTokenDefinitions(additionalTokens)

esday('2024 3').format('YYYY PP')
// Returns '2023-08-14T21:43:12.123'