agent-skills/skills/vueuse-functions/references/useDateFormat.md

category

category
Time

useDateFormat

Get the formatted date according to the string of tokens passed in, inspired by dayjs.

List of all available formats (HH:mm:ss by default):

Format	Output	Description
Yo	2018th	Ordinal formatted year
YY	18	Two-digit year
YYYY	2018	Four-digit year
M	1-12	The month, beginning at 1
Mo	1st, 2nd, ..., 12th	The month, ordinal formatted
MM	01-12	The month, 2-digits
MMM	Jan-Dec	The abbreviated month name
MMMM	January-December	The full month name
D	1-31	The day of the month
Do	1st, 2nd, ..., 31st	The day of the month, ordinal formatted
DD	01-31	The day of the month, 2-digits
H	0-23	The hour
Ho	0th, 1st, 2nd, ..., 23rd	The hour, ordinal formatted
HH	00-23	The hour, 2-digits
h	1-12	The hour, 12-hour clock
ho	1st, 2nd, ..., 12th	The hour, 12-hour clock, sorted
hh	01-12	The hour, 12-hour clock, 2-digits
m	0-59	The minute
mo	0th, 1st, ..., 59th	The minute, ordinal formatted
mm	00-59	The minute, 2-digits
s	0-59	The second
so	0th, 1st, ..., 59th	The second, ordinal formatted
ss	00-59	The second, 2-digits
SSS	000-999	The millisecond, 3-digits
A	AM PM	The meridiem
AA	A.M. P.M.	The meridiem, periods
a	am pm	The meridiem, lowercase
aa	a.m. p.m.	The meridiem, lowercase and periods
d	0-6	The day of the week, with Sunday as 0
dd	S-S	The min name of the day of the week
ddd	Sun-Sat	The short name of the day of the week
dddd	Sunday-Saturday	The name of the day of the week
z	GMT, GMT+1	The timezone with offset
zz	GMT, GMT+1	The timezone with offset
zzz	GMT, GMT+1	The timezone with offset
zzzz	GMT, GMT+01:00	The long timezone with offset

• Meridiem is customizable by defining customMeridiem in options.

Usage

Basic

<script setup lang="ts">
import { useDateFormat, useNow } from '@vueuse/core'

const formatted = useDateFormat(useNow(), 'YYYY-MM-DD HH:mm:ss')
</script>

<template>
  <div>{{ formatted }}</div>
</template>

Use with locales

<script setup lang="ts">
import { useDateFormat, useNow } from '@vueuse/core'

const formatted = useDateFormat(useNow(), 'YYYY-MM-DD (ddd)', { locales: 'en-US' })
</script>

<template>
  <div>{{ formatted }}</div>
</template>

Use with custom meridiem

<script setup lang="ts">
import { useDateFormat } from '@vueuse/core'

function customMeridiem(hours: number, minutes: number, isLowercase?: boolean, hasPeriod?: boolean) {
  const m = hours > 11 ? (isLowercase ? 'μμ' : 'ΜΜ') : (isLowercase ? 'πμ' : 'ΠΜ')
  return hasPeriod ? m.split('').reduce((acc, current) => acc += `${current}.`, '') : m
}

const am = useDateFormat('2022-01-01 05:05:05', 'hh:mm:ss A', { customMeridiem })
// am.value = '05:05:05 ΠΜ'
const pm = useDateFormat('2022-01-01 17:05:05', 'hh:mm:ss AA', { customMeridiem })
// pm.value = '05:05:05 Μ.Μ.'
</script>

Type Declarations

export type DateLike = Date | number | string | undefined
export interface UseDateFormatOptions {
  /**
   * The locale(s) to used for dd/ddd/dddd/MMM/MMMM format
   *
   * [MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl#locales_argument).
   */
  locales?: MaybeRefOrGetter<Intl.LocalesArgument>
  /**
   * A custom function to re-modify the way to display meridiem
   *
   */
  customMeridiem?: (
    hours: number,
    minutes: number,
    isLowercase?: boolean,
    hasPeriod?: boolean,
  ) => string
}
export declare function formatDate(
  date: Date,
  formatStr: string,
  options?: UseDateFormatOptions,
): string
export declare function normalizeDate(date: DateLike): Date
export type UseDateFormatReturn = ComputedRef<string>
/**
 * Get the formatted date according to the string of tokens passed in.
 *
 * @see https://vueuse.org/useDateFormat
 * @param date - The date to format, can either be a `Date` object, a timestamp, or a string
 * @param formatStr - The combination of tokens to format the date
 * @param options - UseDateFormatOptions
 *
 * @__NO_SIDE_EFFECTS__
 */
export declare function useDateFormat(
  date: MaybeRefOrGetter<DateLike>,
  formatStr?: MaybeRefOrGetter<string>,
  options?: UseDateFormatOptions,
): UseDateFormatReturn