How to get the weekday names using Intl?
const weekdayDateMap = {
Mon: new Date('2020-01-06T00:00:00.000Z'),
Tue: new Date('2020-01-07T00:00:00.000Z'),
Wed: new Date('2020-01-08T00:00:00.000Z'),
Thu: new Date('2020-01-09T00:00:00.000Z'),
Fri: new Date('2020-01-10T00:00:00.000Z'),
Sat: new Date('2020-01-11T00:00:00.000Z'),
Sun: new Date('2020-01-12T00:00:00.000Z'),
};
const shortWeekdays = Object.keys(weekdayDateMap);
const getDayOfWeek = (shortName, locale = 'en-US', length = 'short') =>
new Intl.DateTimeFormat(locale, { weekday: length }).format(weekdayDateMap[shortName]);
const getDaysOfWeek = (locale = 'en-US', length = 'short') =>
shortWeekdays.map(shortName => getDayOfWeek(shortName, locale, length));
console.log(getDayOfWeek('Mon', 'de-DE')) // "Mo"
console.log(getDaysOfWeek('de-DE')) // ["Mo", "Di", "Mi", "Do", "Fr", "Sa", "So"]
Note:
If you're calling the Intl.DateTimeFormat
formatter many times a second, it's more efficient to create the formatter once and re-use it.
I was misled because I was using the Intl polyfill, which does not support yet { weekday: "short" }
as option.
Using native Intl implementations works as expected.
my solution in 2021 with es6
/**
* Return list of days
* ð localeName : name of local, f.e. en-GB, default es-MX
* ✅ weekday : formart of weekday short/long (Default)
*/
function daysForLocale(localeName = 'es-MX', weekday = 'long') {
const format = new Intl.DateTimeFormat(localeName, { weekday }).format;
return [...Array(7).keys()]
.map((day) => format(new Date(Date.UTC(2021, 5, day))));
}
// ##############################################################
// testing daysForLocale function
// ##############################################################
console.log(daysForLocale());
// ['domingo','lunes',...,'viernes','sábado']
console.log(daysForLocale('en-GB', 'short'));
// ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri','Sat']
console.log(daysForLocale('ja-JP', 'short'));
// ['日', '月', '火','水', '木', '金','土']