[js: Intl.DateTimeFormat] Built-in DateTime Formatter. #js

intl-datetime-format.js

// https://developer.mozilla.org/ja/docs/Web/JavaScript/Reference/Global_Objects/Intl/DateTimeFormat
// https://dev.classmethod.jp/articles/javascript-intl-datetimeformat-format/

export const intlDateFormat = (date: number|Date) => {
  const formatter = new Intl.DateTimeFormat('ja-JP', {
    year: 'numeric',
    month: '2-digit',
    day: '2-digit',
    weekday: 'short',
  })

  return formatter.format(date).replace(/\//g, '-').split('(').join(' (')
}

intlDateFormat(new Date()) // 2022-03-19 (土)