JSFiddle - React, Tailwind, and code Playground

by Carlos Martinez

HTML

<div id="testA"></div>

<hr/>

<div id="testB"></div>

JavaScript

function LastDays (n, option) {
  let arr = Array.apply(0, Array(n)).map(function(v,i){return i}),
  		weekday = new Array(7);
      
  weekday[0] = "Sunday";
  weekday[1] = "Monday";
  weekday[2] = "Tuesday";
  weekday[3] = "Wednesday";
  weekday[4] = "Thursday";
  weekday[5] = "Friday";
  weekday[6] = "Saturday";
  
  return arr.map(function(n) {
    let date = new Date();
    date.setDate(date.getDate() - n);
    return (function(day, month, year, weekendDay) {
    	switch(option) {
      	case 'weekday': return weekday[weekendDay];
      	default: return [day<10 ? '0'+day : day, month<10 ? '0'+month : month, year].join('/');
      }
    })(date.getDate(), date.getMonth(), date.getFullYear(), date.getDay());
  }).join(', ');
}

document.getElementById("testA").innerHTML = LastDays(3)
document.getElementById("testB").innerHTML = LastDays(5,'weekday')