O'Reilly

Sort an Array of Objects by Property Using sort(fn)

By on  

Believe it or not, there's more to JavaScript than the helper methods and classes they provide your JavaScript library. No, like seriously bro; these JavaScript-given methods do exist. One of those methods, sort, is provided to every Array instance via its prototype. I've used this method once or twice in the history of ever, bro, since I make every effort to ensure proper sort on the server side, but sometimes you may receive a JSON dump and need to sort on the client side.

Most people would assume that sort would take no method and simply sort the basic items within the array:

[1, 3, 9, 2].sort();
	// Returns: [1, 2, 3, 9]
	
[1, "a", function(){}, {}, 12, "c"].sort();
	// Returns: [1, 12, Object, "a", "c", function (){}]

But nay, broseph! If you provide a function expression to the sort method, you can sort objects within the array using simple logic. Let's say you have an array of objects representing persons and you want to sort them by age. Oh yes, it can be done, and quite easily:

[
	{ name: "Robin Van Persie", age: 28 },
	{ name: "Theo Walcott", age: 22 },
	{ name: "Bacary Sagna", age: 26  }
].sort(function(obj1, obj2) {
	// Ascending: first age less than the previous
	return obj1.age - obj2.age;
});
	// Returns:  
	// [
	//	  { name: "Theo Walcott", age: 22 },
	//	  { name: "Bacary Sagna", age: 26  },
	//	  { name: "Robin Van Persie", age: 28 }
	// ]
	

The anonymous function returns whether or not the first object's age is less than the second's, thus sorting the entire array in ascending order by age. Reverse the first and second arguments to sort in descending order.

So brochacho, now you know how to sort an array of objects using JavaScript. Get to it!

Track.js Error Reporting

Recent Features

  • Page Visibility API

    One event that's always been lacking within the document is a signal for when the user is looking at a given tab, or another tab. When does the user switch off our site to look at something else? When do they come back?...

  • How to Create a Twitter Card

    One of my favorite social APIs was the Open Graph API adopted by Facebook.  Adding just a few META tags to each page allowed links to my article to be styled and presented the way I wanted them to, giving me a bit of control...

Incredible Demos

  • Introducing MooTools LinkAlert

    One of my favorite Firefox plugins is called LinkAlert. LinkAlert shows the user an icon when they hover over a special link, like a link to a Microsoft Word DOC or a PDF file. I love that warning because I hate the surprise...

  • JavaScript Battery API

    Mozilla Aurora 11 was recently released with a bevy of new features. One of those great new features is their initial implementation of the Battery Status API. This simple API provides you information about the battery's current charge level, its...

Discussion

  1. Boger

    Nice read, never thought to sort objects this way. but man broseph and brochacho got me laugh to death :D

  2. champi

    Great ! how could I do this in PHP ?

  3. A little bit late, but it still may be useful… ;)

    In PHP, it is almost the same. Here is the equivalent code:

    $people = array(
      array('name' => 'Robin Van Persie', 'age' => 28),
      array('name' => 'Theo Walcott', 'age' => 22),
      array('name' => 'Bacary Sagna', 'age' => 26)
    );
    
    usort($people, function($a, $b) {
      return $a['age'] - $b['age'];
    });
    
    var_dump($people);
    

    More informations: http://php.net/manual/fr/function.usort.php

  4. Anil Gautam

    Hey I am tring your code but its not working.

  5. mauro

    hi, i have tryed to bud a sort function by attributes a lot really, and finally i find this blog, your code work for me if the attribute is a number not if it is a string, why? i have to do something in that case? really thank you

Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!

Recently on David Walsh Blog

  • Loading Static Templates for Intern Testing

    I use Intern by SitePen for all of my JavaScript functional testing.  Intern has loads of features other functional test frameworks don't and it's completely Promise-based -- something I got very used to when I used the Dojo Toolkit every day. Async test creation can...

  • Convert Video to mp3

    Let's all be honest for a moment:  we've all ... not paid for ... music.  Whether it was via a file sharing app like Kazaa or Napster, or it was downloading and seeding on bittorrent, or maybe even downloading a music video and ripping its audio,...

  • Sort git Branches by Date

    I'll be first person to admit I don't do as much git repository maintenance as I should.  I rarely delete branches which have been merged, so a git branch execution shows me a mile-long list of branches that likely aren't relevant.  The best way to find branches I've recently...

  • Best Tools and Resources for Web Professionals in 2015

    Looking for the right resources to help you satisfy the needs of your clients? On the lookout for the best tools to help you increase your revenue? Searching for the right software to help you improve your business? Well, then you’ve come to the right place....

  • JavaScript Polling

    Polling with JavaScript is one of those ugly but important functions within advanced front-end user experience and testing practices.  Sometimes there isn't the event you can hook into to signify that a given task is complete, so you need to get your hands dirty and simply poll for...