javascript datetime to string and back to datetime?

Question

if you had to store the current javascript datetime in a string what would it look like and could you convert it back to a datetime for javascript to read?

What I am trying is not working given the current xml string of Tue Dec 23 12:02:08 EST 2014

var xmlImagePath = $(this).find('pathName').text();

var xmlStartTime = $(this).find('startTime').text();
xmlStartTime = new Date(xmlStartTime);

var fortnightAway = new Date(xmlStartTime);
var numberOfDaysToAdd = 14;
fortnightAway.setDate(fortnightAway.getDate() + numberOfDaysToAdd);


if (fortnightAway < xmlStartTime) {
    alert("here");
}

I do not believe xmlStartTime = new Date(xmlStartTime); is setting the xmlStartTime to a datetime object..

Also, What is the correct format to store the datetime into the xml so that it is easier to test later?

Answer 1

One easy way to serialize dates is to use JSON.stringify and JSON.parse:

var serialized = JSON.stringify(new Date());

var deserialized = new Date(JSON.parse(serialized));

If you don't have the JSON object available, you can do this, which is essentially the same, but with less nested code:

var iso = (new Date()).toISOString();

var dateObj = new Date(iso);

And if you don't have .toISOString (IE 8 or earlier), there is a polyfill here.

Answer 2

Have a look at moment.js library. If you are able to use an external library, this one will save you many headaches dealing with times in javascript. I have a fiddle that demonstrates many possibilities, and I added your example to the end of the list in this fiddle:

http://jsfiddle.net/JamesWClark/9PAFg/

For example, moment('Tue Dec 23 12:02:08 EST 2014').format() will output 2014-12-23T11:02:08-06:00 from which you should easily be able to create a DateTime object.

Using an example from your code, you might try this:

var xmlStartTime = moment($(this).find('startTime').text());
xmlStartTime = new Date(xmlStartTime);