Get last day of the month from '2015-02-23' string (javascript)

Question

I have a string that represents a date in this format: 2015-02-23

I need to use this date to get the last day of the month. How should I do the necessary conversions to achieve that?

Answer 1

Here's a function that should work for you:

function getLastDayInMonth(s) {
  var date = new Date(s);
  var lastDate = date;
  var month = date.getMonth();
  
  while (date.getMonth() == month) {
    lastDate = date;
    date = new Date(lastDate.getTime() + 1000 * 60 * 60 * 24); //add 1 day
  }
  return lastDate.toDateString();
}

var lastDay = getLastDayInMonth('2015-02-23');
alert(lastDay);