Get the first and last date of the previous month in JQuery

Question

I have this script,

 var today = new Date();
 var dd = today.getDate();
 var ffffd = today.getDate()-1;
 var ffffdd = today.getDate()-2;

 var mm = today.getMonth()+         


        

Answer 1

That's the first day of the current month new Date(now.getFullYear(), now.getMonth(), 1) to get the last day of the previous month create a date 1-day earlier: new Date(now.getFullYear(), now.getMonth(), 1 - 1).

To get the first day of the previous month we should substract 1 from the month component new Date(now.getFullYear(), now.getMonth() - 1, 1) but there is an issue if the current month is January (0) and the previous month is December (11). Hence I wrapped the month expression creating a cycle so it always returns a positiove value.

var now = new Date();
var prevMonthLastDate = new Date(now.getFullYear(), now.getMonth(), 0);
var prevMonthFirstDate = new Date(now.getFullYear() - (now.getMonth() > 0 ? 0 : 1), (now.getMonth() - 1 + 12) % 12, 1);

var formatDateComponent = function(dateComponent) {
  return (dateComponent < 10 ? '0' : '') + dateComponent;
};

var formatDate = function(date) {
  return formatDateComponent(date.getMonth() + 1) + '/' + formatDateComponent(date.getDate()) + '/' + date.getFullYear();
};

document.write(formatDate(prevMonthFirstDate) + ' - ' + formatDate(prevMonthLastDate));