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html - Javascript Image onload event binding

So I have this piece of code that loops through an array and load images and notify when the images is loaded.

for (var i = 0; i < arr.length; i++) {                
    var imageObj = new Image();
    imageObj.src = url[i];
    imageObj.onload= (function(i){
                return function(){
                    console.log(i, 'loaded');
                }
            })(i);

}

It works fine. However if I try to do this it won't work

imageObj.addEventListener('onload', function(
    console.log(i, 'loaded');
}, false);

What is the problem? And is there any way for me to avoid using closure in this case?

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1 Answer

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by (71.8m points)

One part of the problem: The event is not called onload, but load.

imageObj.addEventListener('load', function() { /* ... */ }, false);

Other than that, since i changes outside of the event listener function, you need a closure.


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