Intl.NumberFormat Get the Currency Code from a Dynamic Locale?

Question

I am struggling to find a good way to get the Currency Code for Intl.NumberFormat from my locale.

We have the ability for the user to change locale at any time. I need a way to retrieve the currency code based on the selected locale so that I can format appropriately.

let chosenLocale = appSettings.LocaleKey; //Could be anything user chooses en-US, ja-JP, etc..

// THIS DOES NOT EXIST, DOES ANY SUCH MAPPING, LOOKUP, OR LIST EXIST?
let currencyBasedOnLocale = GetCurrencyCodeFromLocale(chosenLocale); 

// WOULD BE COOL IF THERE WAS THIS FOR ALL KNOWN CURRENCIES:
// var localeCurrencyLookup = { "en-US": "USD", "ru-RU" : "RUB", "en-GB" : "GBP", etc... }
// THEN I COULD DO THIS:
// let currencyBasedOnLocale = localeCurrencyLookup[chosenLocale] || "USD"; 

var formatter = new Intl.NumberFormat(chosenLocale, {
    style: 'currency',
    currency: currencyBasedOnLocale
});
return formatter.format(value);

So does anyone know if such a mapping of locales to currency codes exist? Or is there some other way I can find the currency code based on the locale? I feel like this is a huge oversite to not have a locale to currency mapping. Perhaps most sites only support a few locales, leaving the developer to hash it out manually. I do not mind typing out a json lookup mapping object, but I do not even know where to go to see which locales map to which currency code.

lalan21j · Answer 1 · 2023-08-03T04:12:33.643

From my vue:

import { formatAmount } from 'Composables/Utils/currency'
console.log(formatAmount(15008.36, 'en-US', 'USD'))

From my ts

export const formatAmount = (amount:number, getLocale:string, getCurrency:string) => {
  const locale = getLocale
  const currency = getCurrency

  const formats = new Intl.NumberFormat(locale, {
    style: 'currency',
    currency,
    maximumFractionDigits: 2
  })

  return formats.format(amount)
}

result

$15,008.36

Use undefined in the first argument from Intl.NumberFormat to use the system locale (the user's locale).

Intl.NumberFormat Get the Currency Code from a Dynamic Locale?

1 Answers1