Preloading images with JavaScript

Question

Is the function I wrote below enough to preload images in most, if not all, browsers commonly used today?

function preloadImage(url)
{
    var img=new Image(         


        

Answer 1

Yes this will work, however browsers will limit(between 4-8) the actual calls and thus not cache/preload all desired images.

A better way to do this is to call onload before using the image like so:

function (imageUrls, index) {  
    var img = new Image();

    img.onload = function () {
        console.log('isCached: ' + isCached(imageUrls[index]));
        *DoSomething..*

    img.src = imageUrls[index]
}

function isCached(imgUrl) {
    var img = new Image();
    img.src = imgUrl;
    return img.complete || (img .width + img .height) > 0;
}