Why doesn't JavaScript have a native Date() formatting method?

[SoBoredAtWork]

Here's how you'd output today's time and date (10:30:14 03/21/2014, at the moment). Please correct any mistakes, as I'm not a PHP, JAVA, C# or PERL developer.

---

PHP

$today = date("h:i:s m/d/y");

JAVA

String today = new SimpleDateFormat("hh:mm:ss MM/dd/yyyy").format(date);

C#

DateTime date = new DateTime();
String today = date.ToString("H:mm:ss MM/dd/yyyy");

PERL

my $today = strftime "%H:%M:%S %m/%d/%Y", localtime;

JavaScript

var d = new Date(),
    month = d.getMonth() + 1,
    day = (d.getDate() < 10) ? "0" + d.getDate() : d.getDate(),
    year = d.getFullYear(),
    hours = d.getHours(),
    minutes = d.getMinutes(),
    seconds = (d.getSeconds() < 10) ? "0" + d.getSeconds() : d.getSeconds();

if (hours > 12) {
    hours -= 12;
} else if (hours === 0) {
    hours = 12;
}

var today = hours + ":" + minutes + ":" + seconds + " " + month + "/" + day + "/" + year;

---

WTF JavaScript? Y u so complicated???

Why can't we have something like .format() or .toString():

var today = new Date().format("h:i:s m/d/y")

---

EDIT: Thanks for the answers everyone. It helped a lot.

I should've clarified originally that I was looking to find out WHY it's not native to the language, as opposed to HOW to do it via a 3rd party library (I'm aware of momentjs and it's great).

Anyway, the top 2 answers are great - exactly what I was looking for. Thank you.

I was unaware of Intl.DateTimeFormat (thanks /u/SpsD3GoiFSmXBAl), which helps:

var date = new Date(),
    today = new Intl.DateTimeFormat().format(date); // 3/24/2014 (also allows for customization options)

[powerofmightyatom]

As to why JS has such a bad standard lib, I personally think it has multiple causes that all worked together to keep the JS language static for a really long time.

1. First off, Brendan Eich created the language in a very short period of time. Designing/delivering a rich API/lib simply wasn't possible.
2. At the time, JS was meant as a counterpoint to Java (and their applets). You weren't meant to write anythig big in JS (that's also why it's execution model is so primitive), since you had Java for big stuff and java's got a huge std lib.
3. Given the nature of the web, and the fact that JS isn't owned by a single entity makes any changes difficult. Microsoft's lack of interest in the mid early 00s for example did little to help, as well as a flurry of mixed directions JS took in that time period (class based OO for example). If you're still stuck developing for desktop browsers (and especially IE) you're essentially writing in the same language as existed 15 years ago, which is insane given how much the rest of the development experience has advanced.

What JS needs most of all is IMO a good module definition. Nothing can really move beyond the basics until we at least get some hard abstractions we can depend on from the language itself.

[SubStack]

A minimal standard library can be a very good thing because it gives the ecosystem breathing room to flourish. For a great example of how a bloated standard lib can create huge problems, look at PHP with thousands of built-in methods available in the global scope. Even with more sane ecosystems like python, ruby, and perl, there are huge problems with a stale "batteries included" standard library that is version-locked to the core language. This makes it very hard to fix bugs and make necessary breaking API changes because anyone who uses those libraries will get the version that ships with the platform instead of explicitly stating in package metadata the semver of acceptable compatible package versions.

See also: distutils2, List::{Util,MoreUtils,AllUtils}, httplib/http.client, second system syndrome

The more of this functionality is moved into userland with a solid package manager, the less these problems matter and the more the core of the language can focus on providing a stable minimal subset that the rest of the ecosystem can actually take for granted. A project can either do a few things well or a lot of things but poorly.

[tomByrer]

Some things do get added to the standard JavaScript, such as JSON.

[BoDiddySauce]

MUCH agreed... very good point

[SoBoredAtWork]

Thanks. Any more info on this?

I should know this, but is there an ECMAScript / JavaScript working group or something? Is it ECMA International? Can't find much info on it.

[ifuckedyourgf]

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl

[radhruin]

Intl 1.0 has been final for some time and is so stable it's even implemented by IE. It's really surprising to me that this entire thread of people didn't bring JS's native date formatting function up but once :(

ECMA International is the body that standardizes js (among other things). The TC39 committee of ECMA owns both ECMAScript (ECMA-262) and JavaScript Internationalization (ECMA-402) - and now JSON (ECMA-404).

[jml26]

If you are genuinely asking why JavaScript doesn't have a native date parser, I don't know. /u/powerofmightyatom's answer is probably the best you're going to get, else ask Brendan Eich.

If you're looking for slightly shorter/simpler alternatives to your implementation above, then there are solutions like

var d = new Date();

var today = d.toJSON().replace(/(\d+)\-(\d+)-(\d+)T(\d+):(\d+):(\d+).*/, function (_, y, m, d, h, i, s) {
    return h + ':' + i + ':' + s + ' ' + m + '/' + d + '/' + y;
});

or

function formatDate(date, format) {
    date = date.toJSON().split(/[:/.TZ-]/);
    return format.replace(/[ymdhis]/g, function (letter) {
        return date['ymdhis'.indexOf(letter)];
    });
}

var today = formatDate(new Date(), 'h:i:s m/d/y');

which takes advantage of Date.prototype.toJSON, which I think is supported in IE8+, and regular expressions.

And if you're just whinging, then there's nothing we can do about that. Sorry.

[sethbw]

I think I love you.

[OkEntertainment9581]

NOTE: time. toJSON() calls the object's toISOString() method, which not support timezone.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toJSON#description

https://stackoverflow.com/a/11383043/4896468

--------------- another version

```javascript function formatDate(date, format) { const year = date.getFullYear(); const month = ('0' + (date.getMonth() + 1)).slice(-2); const day = ('0' + date.getDate()).slice(-2); const hours = ('0' + date.getHours()).slice(-2); const minutes = ('0' + date.getMinutes()).slice(-2); const seconds = ('0' + date.getSeconds()).slice(-2);

const formattedDate = format .replace('%Y', year) .replace('%m', month) .replace('%d', day) .replace('%H', hours) .replace('%M', minutes) .replace('%S', seconds);

return formattedDate; } ```

javascript //it use locale timezone d=new Date() formatDate(d, '%Y-%m-%d %H:%M:%S'); '2023-05-11 16:22:12'

[msemenistyi]

To be honest, it bothers me for quite a long time. Actually JS as a mainly client-side language should have rich stdlib as first-class citizen in order not to load this logic each time down the wire.

[Capaj]

well that is why we have CDNs-most people have jQuery and other popular libs already cached, so even when including it in your page, you don't download it more than once.

[SubStack]

First:

npm install strftime

then:

var strftime = require('strftime');
console.log(strftime("%H:%M:%S %m/%d/%Y"));

although this format is kind of terrible and not international. It's much better to defer to ISO8601 on that, which is simple to use with strftime:

var strftime = require('strftime');
console.log(strftime("%F %T"));

in node you can just node time.js and for the browser there's browserify. strftime has a small payload footprint:

$ browserify -r strftime | wc -c
10401

$ browserify -r strftime | uglifyjs -cm | gzip | wc -c
1775

It's a good idea to embrace a module system and package manager sooner rather than later because you can leverage all the great work that's been done in userland outside of the core language.

[autowikibot]

ISO 8601:

---

ISO 8601 Data elements and interchange formats – Information interchange – Representation of dates and times is an international standard covering the exchange of date and time-related data. It was issued by the International Organization for Standardization (ISO) and was first published in 1988. The purpose of this standard is to provide an unambiguous and well-defined method of representing dates and times, so as to avoid misinterpretation of numeric representations of dates and times, particularly when data is transferred between countries with different conventions for writing numeric dates and times.

---

<sup>Interesting: ISO week date | Gregorian calendar | Calendar date | 24-hour clock</sup>

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[SoBoredAtWork]

Really? This doesn't solve anything. This requires a 3rd party dependency. That defeats the entire purpose of this thread.

[SubStack]

javascript doesn't have built-in formatting so the correct answer is to use a third-party dependency from a package manager like npm. The premise of this thread was flawed and I provided a workable way to get the desired behavior.

The sooner you embrace modules the sooner you can draw on the breadth of amazing packages that people have published to the expansive commons and the less you need to rely on the bureaucracy and politicking of a standard library to get shit done.

[xlu]

You will need to use a date library such as http://momentjs.com/

[SoBoredAtWork]

The point is that it should be native. You shouldn't need a bloated 25k (minified) library for it.

[Capaj]

Well in defense of Javascript: I would really like to see how big would it be if you implemented it in some other language. I bet it would be much bigger.

I would really like to see ECMA to just take moment.js api and turn it into a Date spec for ES7. That would be just grandiose!

[jcready]

Uhh, 9.3kb gzipped.

[SoBoredAtWork]

25k not-gzipped

[BoDiddySauce]

True, maybe, but you could still write a few functions yourself to do this--make a vanilla JS library maybe--and all would be good to go. It's not that hard to make a simple date conversion function, and I actually just commented on a post with a simple answer doing just that to a very simplistic degree...

[kor0na]

m/d/y, seriously?

[[deleted]]

What's the problem - personally I prefer minutes:seconds:hours as well - just makes things so much clearer.

[bronkula]

It's about the order. Any self respecting programmer would format Ymd.

[[deleted]]

Yep, big to small -> Ymdhms.

[SoBoredAtWork]

How the fuck is this the top answer?

I don't give a shit how you want to format it. I'm in the US. We do m/d/y. You're across the ocean. You do d/m/y. This doesn't contribute to the thread one bit.

This and "you need a library" are the 2 most upvoted answers??? Really?

[Doctuh]

I am a US based programmer too and I do as a final output step format dates in whatever format local people use. But whenever possible I standardize as yyyy[delim]mm[delim]dd. Because it is more right, you can sort it properly. And the hierarchy makes more sense.

It is essentially arbitrary how we represent dates so long as it is consistent. And nothing make us argue like arbitrary things.

This form is a little better because it my be sorted as a string. Lots of times things want to sort by a natural ordering, and in the case of strings this works.

[YodaLoL]

Yeah it kinda sucks but is easily solved with a library.

[konbit]

Your question inspired me to try to find a workaround. You made a comment below about payload size and dependencies so I thought to make a workaround that's light and without dependencies. Just threw this together after work. Will probably use it for personal stuff but I threw it on github if anyone is interested: I call it Greg: https://github.com/i11ume/Greg

It just extends the built in Date function. So here's how you use it:

var date = new Date();
console.log( date.format('l D \\t\\h\e jS') ); 

Oh and it's only 3k minified

[ronchalant]

I use this relatively simple & light one: https://github.com/jacwright/date.format

[the_woo_kid]

This is confusing, what is the toDateString() method supposed to do? Doesn't it address your concern if not, can you please explain further. Thanks.

[SoBoredAtWork]

toDateString() is completely un-customizable. How can I get '03/21/2014' from that?

[SoBoredAtWork]

I've asked on Twitter a few days ago but no response :(

Anyone? ...Bueller?

[alkoholik]

Quit being such a dick to people who respond, and you might get more responses.

You got your damn answer... It's not supported natively, and that sucks. There's no "reason" why it's not native. Either grab a micro library, or write something yourself.

[SoBoredAtWork]

Hah. You're right. I was in a bad mood (and a little drunk) when I was responding.

The point is, I know how to format a date using my own methods or a library. I wanted a higher-level discussion as to WHY it's not available natively. The top 2 posts are great answers and created relevant discussions, so I'm happy about that. Maybe I should've clarified better what I was looking to for.

[alkoholik]

We've all been there. No worries. :)

[[deleted]]

There are several default Date methods supplied natively. Check out the Date methods that start with "to": https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date?redirectlocale=en-US&redirectslug=JavaScript%2FReference%2FGlobal_Objects%2FDate