dtfm

Locale-agnostic date formatting utilities

Date formatting

formatDate(new Date(), '{YYYY}-{MM}-{DD} {HH}:{mm}:{ss}');
// = 2022-07-19 12:34:56

List of placeholders

| Placeholder | Value | |-------------|-------| | {Y} | Year | | {YY} | Year, zero-prefixed when shorter than 2 digits | | {YYYY} | Year, zero-prefixed when shorter than 4 digits | | {yy} | Year, last 2 digits zero-prefixed when shorter than 2 digits | | {YE} | Year of a calendar era (specified by AD/BC or CE/BCE) | | {E} | Christian era: AD/BC | | {CE} | Common Era: CE/BCE | | {M} | Month | | {MM} | Month, zero-prefixed when shorter than 2 digits | | {MMM} | Month abbreviation | | {D} | Day | | {DD} | Day, zero-prefixed when shorter than 2 digits | | {H} | Hours | | {HH} | Hours, zero-prefixed when shorter than 2 digits | | {h} | 12h-clock hours | | {hh} | 12h-clock hours, zero-prefixed when shorter than 2 digits | | {a} | Day period: AM/PM | | {m} | Minutes | | {mm} | Minutes, zero-prefixed when shorter than 2 digits | | {s} | Seconds | | {ss} | Seconds, zero-prefixed when shorter than 2 digits | | {ms} | Milliseconds, zero-prefixed when shorter than 3 digits | | {tz} | Time zone | | {WD} | Week day abbreviation | | {iso} | Local time zone ISO date string | | {isoDate} | Date (= {YYYY}-{MM}-{DD}) | | {isoTime} | Time (= {HH}:{mm}:{ss}) | | {isoTimeMs} | Time with milliseconds |

The following unformatted date components are also available as placeholder values: timestamp, year, month, day, hours, hours12 (12h-clock hours), minutes, seconds, milliseconds, weekDay, timezoneOffset, input (the first argument of the formatDate() call).

Using external locale-specific formats

formatDate(new Date(), customLocale.fullDate);
// = þriðjudagur 19. júlí 2022

// custom-locale.js (outside the package)
const customWeekDays = [
    'sunnudagur',
    'mánudagur',
    'þriðjudagur',
    'miðvikudagur',
    'fimmtudagur',
    'föstudagur',
    'laugardagur',
];
const customMonths = [
    'janúar',
    'febrúar',
    'mars',
    'apríl',
    'maí',
    'júní',
    'júlí',
    'ágúst',
    'september',
    'október',
    'nóvember',
    'desember',
];
const customFullDateFormat = {
    template: '{WD} {D}. {MMM} {Y}',
    transform: {
        WD: ({weekDay}) => customWeekDays[weekDay],
        MMM: ({month}) => customMonths[month - 1],
    },
};

export const customLocale = {
    fullDate: customFullDateFormat,
};

Dynamic templates

let eraTemplate = ({E}) => E === 'AD' ? '{E} {YE}' : '{YE} {E}';

formatDate('2022-07-19', eraTemplate);
// = AD 2022

formatDate(-62200000000000, eraTemplate);
// = 3 BC

Durations

formatDuration(123456);
// = 2'03.456"