// The "callback" argument is called with either true or false
// depending on whether the image at "url" exists or not.
function imageExists(url, callback) {
var img = new Image();
img.onload = function() { callback(true); };
img.onerror = function() { callback(false); };
img.src = url;
}
// Sample usage
var imageUrl = 'http://www.google.com/images/srpr/nav_logo14.png';
imageExists(imageUrl, function(exists) {
console.log('RESULT: url=' + imageUrl + ', exists=' + exists);
});
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