NaN javascript error when calculating between dates with timestamp

Question

I would like to begin by saying i looked at multiple threads in this forum before posting. Wasnt able to find my solution :(

Issue: getting a NaN error when trying to find the difference between two dates with a timestamp from two textboxes.

The date format i'm using is DDMMYYYY HH:MM - 27/01/2015 00:00 code below.

thank you in advance for this super helpful forum :)

function stringToDate(s) {
    var dateParts = s.split(' ')[0].split('-'); 
    var timeParts = s.split(' ')[1].split(':');
    var d = new Date(dateParts[0], --dateParts[1], dateParts[2]);
    d.setHours(timeParts[0], timeParts[1], timeParts[2]);

    return d;
}

function test() {
    var a = textbox_1.value;
    var b = textbox_2.value;
    alert(stringToDate(a) - stringToDate(b));
}

Answer 1

Your date has / as separator but you are splitting the string on -. Change

var dateParts = s.split(' ')[0].split('-');

to

var dateParts = s.split(' ')[0].split('/');

Also, your time part has only hours and minutes, so there is no timeParts[2] present, just remove it from the setHours() call. Like this:

d.setHours(timeParts[0], timeParts[1])

Fiddle: http://jsfiddle.net/2evj59d1/

EDIT
Your code returns the difference in milliseconds. To convert it into date format just change

alert(stringToDate(a) - stringToDate(b));

to

alert(new Date(stringToDate(a) - stringToDate(b)));

Answer 2

The code is trying to parse a time in the format HH:MM:SS. Skip the third part:

d.setHours(timeParts[0], timeParts[1]);

Answer 3

You can convert the date into milliseconds, get the difference and get the date back.

Fiddle

JSCode:

var a = new Date();
a.setDate(15);
a = a.getTime();
var b = new Date();
b.setDate(32);
b = b.getTime();
var c = b - a;
var date = new Date(c);
alert(date.getDate() - 1);

Answer 4

for those who may have stumbled upon my post, i found my answer at the link below by user benjour. How do I get the difference between two Dates in JavaScript?