How can I use the Date() use correctly in javascript?

Question

I am having problem using Date Object, when I try to parse unix-timestamp.

example:

//I am receiving json data that contains Unix-Timestamp like 1348514100000

var unixTimestamp = data.timestamp; //1348514100000
var date = new Date(unixTimestamp);
console.log(date.getDay()); // is wrong..

and example 2:

var unixTimestamp = data.timestamp; //1348514100000
var date = new Date();
date = date.setDate(unixTimestamp);
console.log(date.getDay()); // still wrong..

I have tried to parse string-timestamp to convert int with

var intUT = parseInt(unixTimestamp);

but still not the correct date&time.. I have really no idea what to do. How can I get the correct date and time from this unix timestamp?

Thank you!

You should explain what you mean by "wrong", as that is exactly how you use the Date() object in JavaScript. — Pointy
– Pointy, Commented Sep 24, 2012 at 13:44
Well what is it that you expect? When I pass that number to the Date() constructor, I get "Mon Sep 24 2012 14:15:00 GMT-0500 (CDT)", which looks right to me. — Pointy
– Pointy, Commented Sep 24, 2012 at 13:46
JavaScript interprets the time stamp as being a Universal Time value. It then constructs a Date object reflecting the local time of the browser (or wherever you're running the JavaScript). If I were in California, then it would have been "12:15:00 GMT-0700 (PDT)". — Pointy
– Pointy, Commented Sep 24, 2012 at 13:47
Ahh -- make sure you're passing a number and not a string! Try new Date(+unixTimestamp) in other words ... — Pointy
– Pointy, Commented Sep 24, 2012 at 13:50
Well formatting the date is a different problem :-) JavaScript doesn't have much direct support for date formatting, but you can build that yourself from the various "getter" functions on Date objects (getFullYear(), getDate(), getMonth(), etc). Note that the month is a number from 0 to 11, not 1 to 12! — Pointy
– Pointy, Commented Sep 24, 2012 at 13:52

Tomasz Nurkiewicz · Accepted Answer · 2012-09-24 13:57:12Z

Your code is completely fine, the only issue might be with incorrect type. Trying this:

new Date(+"1348514100000")

gives me Mon Sep 24 2012 21:15:00 GMT+0200 (CEST), others reported Mon Sep 24 2012 14:15:00 GMT-0500 (CDT) and 12:15:00 GMT-0700 (PDT). According to http://www.epochconverter.com it is Mon, 24 Sep 2012 19:15:00 GMT.

Note that all these dates represent exactly the same point in time. The time zone difference (and thus different hour) is only due to stupid Date.toString() implementation (mistake copied from Java language).

The only portable and built-in way to deal with such dates is to either operate on epoch time (milliseconds) or use getUTC*() family of methods:

new Date(+"1348514100000").getUTCHours()

The code above will always return 19 (GMT time), irrespective to browser/OS time zone.

Collectives™ on Stack Overflow

How can I use the Date() use correctly in javascript?

1 Answer 1

Comments

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Related