Skip to content

Instantly share code, notes, and snippets.

Created June 3, 2012 19:30
Show Gist options
  • Save eirikbacker/2864711 to your computer and use it in GitHub Desktop.
Save eirikbacker/2864711 to your computer and use it in GitHub Desktop.
addEventListener polyfill for IE6+
//addEventListener polyfill 1.0 / Eirik Backer / MIT Licence
(function(win, doc){
if(win.addEventListener)return; //No need to polyfill
function docHijack(p){var old = doc[p];doc[p] = function(v){return addListen(old(v))}}
function addEvent(on, fn, self){
return (self = this).attachEvent('on' + on, function(e){
var e = e || win.event;
e.preventDefault = e.preventDefault || function(){e.returnValue = false}
e.stopPropagation = e.stopPropagation || function(){e.cancelBubble = true}, e);
function addListen(obj, i){
if(i = obj.length)while(i--)obj[i].addEventListener = addEvent;
else obj.addEventListener = addEvent;
return obj;
addListen([doc, win]);
if('Element' in win)win.Element.prototype.addEventListener = addEvent; //IE8
else{ //IE < 8
doc.attachEvent('onreadystatechange', function(){addListen(doc.all)}); //Make sure we also init at domReady
})(window, document);
Copy link

@Daniel-Hug: Yeah, that jumped out at me too. It's not just unnecessary, it's misleading. Fortunately, the order in which the various things are added to the environment record for the variable environment when entering function code is very clear in the spec and seems to be well-followed by implementations.

Copy link

irbian commented Jul 9, 2014

Can fn be empty? that make sense? While coding I found a "Object don´t accept this action" and checking the value show a fn = {}

Copy link

I've updated the code.
This code supported removeEventListener.

addEventListener & removeEventListener polyfill 1.1 - Qiita

Please rate.

Copy link

@sounisi5011 Great stuff, I took the liberty to add your work in Git to give the opportunity for anyone to contribute:

I started using it in one of my projects and so far no issues.

Copy link

oshx commented Jul 19, 2017

The original version, it occurs an error while use it with jQuery in lte IE 8 after bundled via WebPack with jQuery. It fills only addEventListener. When jQuery loaded then detect eventListener via only addEventListener then jQuery try to use removeEventListener that you can see on Ready.js in jQuery 1.12.4.

@nbouvrette Could I sure to use your version for "DOMContentLoaded" also?

Copy link

Fine work, thank you. There may be an issue with line 11:, e);

In case that fn is an empty object. When running IE11 in emulation mode for IE8, then it reports that this method is unavailable:

Das Objekt unterstützt diese Aktion nicht.

Adding a condition helps:

if ("call" in fn), e);

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment