.toLocaleString()

Returns a string representing the elements of the array formatted according to locale conventions.

Examples:

let prices = [1000.99, 2000.39, 3000.79];
let priceStrings = prices.toLocaleString('en-US', { style: 'currency', currency: 'USD' });
console.log(priceStrings); // '$1,000.99,$2,000.39,$3,000.79'

let dates = [new Date('2021-01-01'), new Date('2022-02-02')];
let dateStrings = dates.toLocaleString('en-GB');
console.log(dateStrings); // '01/01/2021, 02/02/2022'