addEventListener in Internet Explorer

What is the equivalent to the Element Object in Internet Explorer 9?

if (!Element.prototype.addEventListener) {
    Element.prototype.addEventListener = function() { .. } 
} 

How does it works in Internet Explorer?

If there's a function equal to addEventListener and I don't know, explain please.

Any help would be appreciated. Feel free to suggest a completely different way of solving the problem.

addEventListener is the proper DOM method to use for attaching event handlers.

Internet Explorer (up to version 8) used an alternate attachEvent method.

Internet Explorer 9 supports the proper addEventListener method.

The following should be an attempt to write a cross-browser addEvent function.

function addEvent(evnt, elem, func) {
   if (elem.addEventListener)  // W3C DOM
      elem.addEventListener(evnt,func,false);
   else if (elem.attachEvent) { // IE DOM
      elem.attachEvent("on"+evnt, func);
   }
   else { // No much to do
      elem["on"+evnt] = func;
   }
}

John Resig, author of jQuery, submitted his version of cross-browser implementation of addEvent and removeEvent to circumvent compatibility issues with IE's improper or non-existent addEventListener.

function addEvent( obj, type, fn ) {
  if ( obj.attachEvent ) {
    obj['e'+type+fn] = fn;
    obj[type+fn] = function(){obj['e'+type+fn]( window.event );}
    obj.attachEvent( 'on'+type, obj[type+fn] );
  } else
    obj.addEventListener( type, fn, false );
}
function removeEvent( obj, type, fn ) {
  if ( obj.detachEvent ) {
    obj.detachEvent( 'on'+type, obj[type+fn] );
    obj[type+fn] = null;
  } else
    obj.removeEventListener( type, fn, false );
}

Source: http://ejohn.org/projects/flexible-javascript-events/

I'm using this solution and works in IE8 or greater.

if (typeof Element.prototype.addEventListener === 'undefined') {
    Element.prototype.addEventListener = function (e, callback) {
      e = 'on' + e;
      return this.attachEvent(e, callback);
    };
  }

And then:

<button class="click-me">Say Hello</button>

<script>
  document.querySelectorAll('.click-me')[0].addEventListener('click', function () {
    console.log('Hello');
  });
</script>

This will work both IE8 and Chrome, Firefox, etc.

As Delan said, you want to use a combination of addEventListener for newer versions, and attachEvent for older ones.

You'll find more information about event listeners on MDN. (Note there are some caveats with the value of 'this' in your listener).

You can also use a framework like jQuery to abstract the event handling altogether.

$("#someelementid").bind("click", function (event) {
   // etc... $(this) is whetver caused the event
});

Here's something for those who like beautiful code.

function addEventListener(obj,evt,func){
    if ('addEventListener' in window){
        obj.addEventListener(evt,func, false);
    } else if ('attachEvent' in window){//IE
        obj.attachEvent('on'+evt,func);
    }
}

Shamelessly stolen from Iframe-Resizer.

addEventListener is supported from version 9 onwards; for older versions use the somewhat similar attachEvent function.

EDIT

I wrote a snippet that emulate the EventListener interface and the ie8 one, is callable even on plain objects: https://github.com/antcolag/iEventListener/blob/master/iEventListener.js

OLD ANSWER

this is a way for emulate addEventListener or attachEvent on browsers that don't support one of those
hope will help

(function (w,d) {  // 
	var
		nc	= "", nu    = "", nr    = "", t,
		a	= "addEventListener",
		n	= a in w,
		c	= (nc = "Event")+(n?(nc+= "", "Listener") : (nc+="Listener","") ),
		u	= n?(nu = "attach", "add"):(nu = "add","attach"),
		r	= n?(nr = "detach","remove"):(nr = "remove","detach")
/*
 * the evtf function, when invoked, return "attach" or "detach" "Event" functions if we are on a new browser, otherwise add "add" or "remove" "EventListener"
 */
	function evtf(whoe){return function(evnt,func,capt){return this[whoe]((n?((t = evnt.split("on"))[1] || t[0]) : ("on"+evnt)),func, (!n && capt? (whoe.indexOf("detach") < 0 ? this.setCapture() : this.removeCapture() ) : capt  ))}}
	w[nu + nc] = Element.prototype[nu + nc] = document[nu + nc] = evtf(u+c) // (add | attach)Event[Listener]
	w[nr + nc] = Element.prototype[nr + nc] = document[nr + nc] = evtf(r+c) // (remove | detach)Event[Listener]
	
})(window, document)

I would use these polyfill https://github.com/WebReflection/ie8

<!--[if IE 8]><script
  src="//cdnjs.cloudflare.com/ajax/libs/ie8/0.2.6/ie8.js"
></script><![endif]-->