I have a lot of code that use addEventListener in minified libraries, files ..., but I need to make work this code in IE8, so replacing addEventListener with addEvent:

 /*
  * Register the specified handler function to handle events of the specified
  * type on the specified target. Ensure that the handler will always be
  * invoked as a method of the target.
  */
 function addEvent(type, handler) {
     if (this.addEventListener)
         this.addEventListener(type, handler, false);
     else {
         this.attachEvent("on" + type,
             function(event) {
                 return handler.call(this, event);
             });
     }
 }

I can "override" window.addEventListener, but how can I override this method in the other objects?

Thanks in advance Regards

I have a lot of code that use addEventListener in minified libraries, files ..., but I need to make work this code in IE8, so replacing addEventListener with addEvent:

 /*
  * Register the specified handler function to handle events of the specified
  * type on the specified target. Ensure that the handler will always be
  * invoked as a method of the target.
  */
 function addEvent(type, handler) {
     if (this.addEventListener)
         this.addEventListener(type, handler, false);
     else {
         this.attachEvent("on" + type,
             function(event) {
                 return handler.call(this, event);
             });
     }
 }

I can "override" window.addEventListener, but how can I override this method in the other objects?

Thanks in advance Regards

• javascript
• internet-explorer-8

• you can define window.addEventListener in IE to work as the W3 one, so that all code uses the same code, and new browsers use the native mand instead of forking each time. – dandavis Commented Oct 13, 2014 at 19:57
• window.addEventListener = window.addEventListener || function addEvent(type, handler) { this.attachEvent("on" + type, function (event) { return handler.call(this, event); }); } – dandavis Commented Oct 13, 2014 at 19:59
• if i use above code only add addEventListener to window? I need to all objects – Diomedes Commented Oct 13, 2014 at 20:17
• yeah, the above is just for window. you should use Object.defineProperty to do the same type of thing on Element.prototype (only for IE!). – dandavis Commented Oct 13, 2014 at 20:48

1 Answer 1

To access it the same way as you would in modern browsers, you'll want to add the method to Window, HTMLDocument, and Element prototypes.

(function(){
    if (!("addEventListener" in window)) {
        function addEventListener(type, handler) {
            var _this = this;              
            this.attachEvent("on" + type, function(){
                handler.call(_this, window.event);  
            });
        }
        Window.prototype.addEventListener = addEventListener;
        HTMLDocument.prototype.addEventListener = addEventListener;
        Element.prototype.addEventListener = addEventListener;
    }
})();

<sub>Note: while we've normalized access to the function and addressed the this issue, we haven't normalized the event to w3c standards. So, it will be missing properties like event.target, event.relatedTarget, etc.

Check out Mozilla's addEventListener() shim.</sub>