How to subtract the future date from the current one?

Question

JavaScript

How to subtract the current date from the future and display it? Tried like this, but in the console: "NaN";

var date        = new Date();
  var actionDate  = "31/12/2015";
  var day         = date.getDate();
  var month       = date.getMonth() + 1;
  var year        = date.getFullYear();  
  var currentDate = day + "/" + month + "/" + year;
  var timeRemaining = actionDate - currentDate;
  console.log(timeRemaining);

Answer 1

if in one line then
it's in days

Answer 2

You are inventing some kind of bicycle from cast iron and mercury.

var curDate = new Date() - current
var accDate = new Date(year,month,day) - target

And read how you want. Get the difference in ticks.

Answer 3

If a lot of work is expected with dates, you can consider using the Moment.js library