JSFiddle - React, Tailwind, and code Playground

by 규연 황

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.29.1/moment.min.js"></script>

JavaScript

function getWeekofMonth(startWeek) {
  let getDate = moment(startWeek, "YYYY.MM.DD");
  let getYear = getDate.format("YYYY");
  let getMonth = getDate.format("M");
  let middleDate = getDate.add(3, 'days');
  let weekMinus = 1;
  let firstDayNumber = moment(middleDate).startOf("month").day();
  if(5 <= firstDayNumber) {weekMinus = 0;}
  let currentDay = Number(moment(middleDate).format('D'));
  let weekofMonth = (currentDay + firstDayNumber - 2) / 7;
  weekofMonth = parseInt(weekofMonth + weekMinus);
  return `${getYear}년 ${getMonth}월 ${weekofMonth}주차`;
}

const getdate = getWeekofMonth("2020.12.31")
console.log(getdate)