Cross-brower window onload method with Javascript

Question

With Javascript, I'm wondering what's the current best way to load my code onto the page (without jQuery) after the rest of the page has been loaded. So like a window.onload...

I was looking at several options but they all seem outdated and not-completely cross-browser friendly.

Does this look like it would be best? It does work, I got it from online tools but I think it spawned from Scott Andrews

 function addEvent(obj, evType, fn) { 
 if (obj.addEventListener){ 
   obj.addEventListener(evType, fn, false); 
   return true; 
 } else if (obj.attachEvent){ 
   var r = obj.attachEvent("on"+evType, fn); 
   return r; 
 } else { 
   return false; 
 } 
}

function init () {
// do something
}

addEvent(window, 'load', init);

Even though it works and passes all my tests and seems quite flexible, I'm a little worried about this approach, because

I don't fully understand it
It seems old, Scott Andrews page is from 2001!
Opera Technical support didn't like it, see "The voice of Opera" on online tools

Is this the best way to do this?

Saul · Accepted Answer · 2010-10-28 21:17:29Z

1

From The Javascript Source

/* This script and many more are available free online at
The JavaScript Source!! http://javascript.internet.com
Created by: Caleb Duke | http://www.askapache.com/ */

//------------------------------------
// heavily based on the Quirksmode addEvent contest winner, John Resig
// addEvent
function addEvent(obj,type,fn){
    if(obj.addEventListener) obj.addEventListener(type,fn,false);
    else 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]);
    }
}

//------------------------------------
// removeEvent
function removeEvent(obj,type,fn){
  if(obj.removeEventListener) obj.removeEventListener(type,fn,false);
  else if(obj.detachEvent){
    obj.detachEvent("on"+type,obj[type+fn]);
    obj[type+fn]=null;
    obj["e"+type+fn]=null;
  }
}

answered Oct 28, 2010 at 21:17

Saul

18k8 gold badges67 silver badges93 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

yekta Over a year ago

Thank you! That's really quite nice, I like it alot. I am curious, however, do I need to utilize removeEvent at all, to keep from leaving an open event in memory or something? What function would I pass to removeEvent? I can't pass the one I just loaded that seems to break stuff.

Saul Over a year ago

You need to remove the event only if you want to get rid of the behavior that element has. So in general, you don't have to. The memory usually gets cleared after the browser leaves the page. PS. You might want to accept answers on your questions, that way you'll get more views on the next question.

yekta Over a year ago

Thanks :) Still getting used to Stack Overflow.

Collectives™ on Stack Overflow

Cross-brower window onload method with Javascript

1 Answer 1

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related