Detecting an image 404 in Javascript - javascript

After a user uploads a file we have to do some additional processing with the images such as resizing and upload to S3. This can take up to 10 extra seconds. Obviously we do this in a background. However, we want to show the user the result page immediately and simply show spinners in place until the images arrive in their permanent home on s3.
I'm looking for a way to detect that a certain image failed to load correctly (404) in a cross browser way. If that happens, we want to use JS to show a spinner in it's place and reload the image every few seconds until it can be successfully loaded from s3.

Handle the <img> element's onerror event.

First option:
<img src="picture1.gif" onerror="this.onerror=null;this.src='missing.gif';"/>
Second option:
<html>
<head>
<script type="text/javascript">
function ImgError(source){
source.src = "/noimage.gif";
source.onerror = "";
return true;
}
</script>
</head>
<body>
<img src="image_example1.jpg" onerror="ImgError(this)" />
</body>
</html>
PS: it's pure javascript! you don't need any libraries. (Vanilla JS)
Example in Fidler
https://jsfiddle.net/dorathoto/8z4Ltzp8/71/

From: http://lucassmith.name/2008/11/is-my-image-loaded.html
// First a couple helper functions
function $(id) {
return !id || id.nodeType === 1 ? id : document.getElementById(id);
}
function isType(o,t) { return (typeof o).indexOf(t.charAt(0).toLowerCase()) === 0;}
// Here's the meat and potatoes
function image(src,cfg) { var img, prop, target;
cfg = cfg || (isType(src,'o') ? src : {});
img = $(src);
if (img) {
src = cfg.src || img.src;
} else {
img = document.createElement('img');
src = src || cfg.src;
}
if (!src) {
return null;
}
prop = isType(img.naturalWidth,'u') ? 'width' : 'naturalWidth';
img.alt = cfg.alt || img.alt;
// Add the image and insert if requested (must be on DOM to load or
// pull from cache)
img.src = src;
target = $(cfg.target);
if (target) {
target.insertBefore(img, $(cfg.insertBefore) || null);
}
// Loaded?
if (img.complete) {
if (img[prop]) {
if (isType(cfg.success,'f')) {
cfg.success.call(img);
}
} else {
if (isType(cfg.failure,'f')) {
cfg.failure.call(img);
}
}
} else {
if (isType(cfg.success,'f')) {
img.onload = cfg.success;
}
if (isType(cfg.failure,'f')) {
img.onerror = cfg.failure;
}
}
return img;
}
And here how to use it:
image('imgId',{
success : function () { alert(this.width); },
failure : function () { alert('Damn your eyes!'); },
});
image('http://somedomain.com/image/typooed_url.jpg', {
success : function () {...},
failure : function () {...},
target : 'myContainerId',
insertBefore : 'someChildOfmyContainerId'
});

just bind the attr trigger on the error event.
$(myimgvar).bind('error',function(ev){
//error has been thrown
$(this).attr('src','/path/to/no-artwork-available.jpg');
}).attr('src',urlvar);

This worked for me (mine is in coffeescript). You'll need to replace with a spinner instead, of course.
checkImages = ->
$("img").each ->
$(this).error ->
$(this).attr("src", "../default/image.jpg")
$(document).on('page:load', checkImages)
I'm guessing the javascript equivalent is something like
function checkImages() {
$("img").each(function() {
$(this).error(function() {
$(this).attr("src", "../default/image.jpg");
});
});
};
$(document).on("page:load", checkImages);

I just did
if ($('#img')[0].naturalWidth > 0) {
as i noticed there was no naturalWidth if the image 404'd.
However, i can understand wanting to use a method above.

Related

Javascript replace SEVERAL broken images until you find a good one [duplicate]

I have a web page that includes a bunch of images. Sometimes the image isn't available, so a broken image is displayed in the client's browser.
How do I use jQuery to get the set of images, filter it to broken images then replace the src?
--I thought it would be easier to do this with jQuery, but it turned out much easier to just use a pure JavaScript solution, that is, the one provided by Prestaul.
Handle the onError event for the image to reassign its source using JavaScript:
function imgError(image) {
image.onerror = "";
image.src = "/images/noimage.gif";
return true;
}
<img src="image.png" onerror="imgError(this);"/>
Or without a JavaScript function:
<img src="image.png" onError="this.onerror=null;this.src='/images/noimage.gif';" />
The following compatibility table lists the browsers that support the error facility:
http://www.quirksmode.org/dom/events/error.html
I use the built in error handler:
$("img").error(function () {
$(this).unbind("error").attr("src", "broken.gif");
});
Edit: The error() method is deprecated in jquery 1.8 and higher. Instead, you should use .on("error") instead:
$("img").on("error", function () {
$(this).attr("src", "broken.gif");
});
In case someone like me, tries to attach the error event to a dynamic HTML img tag, I'd like to point out that, there is a catch:
Apparently img error events don't bubble in most browsers, contrary to what the standard says.
So, something like the following will not work:
$(document).on('error', 'img', function () { ... })
Hope this will be helpful to someone else. I wish I had seen this here in this thread. But, I didn't. So, I am adding it
Here is a standalone solution:
$(window).load(function() {
$('img').each(function() {
if ( !this.complete
|| typeof this.naturalWidth == "undefined"
|| this.naturalWidth == 0 ) {
// image was broken, replace with your new image
this.src = 'http://www.tranism.com/weblog/images/broken_ipod.gif';
}
});
});
I believe this is what you're after: jQuery.Preload
Here's the example code from the demo, you specify the loading and not found images and you're all set:
jQuery('#images img').preload({
placeholder:'placeholder.jpg',
notFound:'notfound.jpg'
});
$(window).bind('load', function() {
$('img').each(function() {
if( (typeof this.naturalWidth != "undefined" && this.naturalWidth == 0)
|| this.readyState == 'uninitialized' ) {
$(this).attr('src', 'missing.jpg');
}
});
});
Source: http://www.developria.com/2009/03/jquery-quickie---broken-images.html
While the OP was looking to replace the SRC, I'm sure many people hitting this question may only wish to hide the broken image, in which case this simple solution worked great for me.
Using Inline JavaScript:
<img src="img.jpg" onerror="this.style.display='none';" />
Using External JavaScript:
var images = document.querySelectorAll('img');
for (var i = 0; i < images.length; i++) {
images[i].onerror = function() {
this.style.display='none';
}
}
<img src='img.jpg' />
Using Modern External JavaScript:
document.querySelectorAll('img').forEach((img) => {
img.onerror = function() {
this.style.display = 'none';
}
});
<img src='img.jpg' />
See browser support for NodeList.forEach and arrow functions.
Here is a quick-and-dirty way to replace all the broken images, and there is no need to change the HTML code ;)
codepen example
$("img").each(function(){
var img = $(this);
var image = new Image();
image.src = $(img).attr("src");
var no_image = "https://dummyimage.com/100x100/7080b5/000000&text=No+image";
if (image.naturalWidth == 0 || image.readyState == 'uninitialized'){
$(img).unbind("error").attr("src", no_image).css({
height: $(img).css("height"),
width: $(img).css("width"),
});
}
});
This is a crappy technique, but it's pretty much guaranteed:
<img onerror="this.parentNode.removeChild(this);">
I couldn't find a script to suit my needs, so I made a recursive function to check for broken images and attempt to reload them every four seconds until they are fixed.
I limited it to 10 attempts as if it's not loaded by then the image might not be present on server and the function would enter an infinite loop. I am still testing though. Feel free to tweak it :)
var retries = 0;
$.imgReload = function() {
var loaded = 1;
$("img").each(function() {
if (!this.complete || typeof this.naturalWidth == "undefined" || this.naturalWidth == 0) {
var src = $(this).attr("src");
var date = new Date();
$(this).attr("src", src + "?v=" + date.getTime()); //slightly change url to prevent loading from cache
loaded =0;
}
});
retries +=1;
if (retries < 10) { // If after 10 retries error images are not fixed maybe because they
// are not present on server, the recursion will break the loop
if (loaded == 0) {
setTimeout('$.imgReload()',4000); // I think 4 seconds is enough to load a small image (<50k) from a slow server
}
// All images have been loaded
else {
// alert("images loaded");
}
}
// If error images cannot be loaded after 10 retries
else {
// alert("recursion exceeded");
}
}
jQuery(document).ready(function() {
setTimeout('$.imgReload()',5000);
});
You can use GitHub's own fetch for this:
Frontend: https://github.com/github/fetch
or for Backend, a Node.js version: https://github.com/bitinn/node-fetch
fetch(url)
.then(function(res) {
if (res.status == '200') {
return image;
} else {
return placeholder;
}
}
Edit: This method is going to replace XHR and supposedly already has been in Chrome. To anyone reading this in the future, you may not need the aforementioned library included.
This is JavaScript, should be cross browser compatible, and delivers without the ugly markup onerror="":
var sPathToDefaultImg = 'http://cdn.sstatic.net/stackexchange/img/logos/so/so-icon.png',
validateImage = function( domImg ) {
oImg = new Image();
oImg.onerror = function() {
domImg.src = sPathToDefaultImg;
};
oImg.src = domImg.src;
},
aImg = document.getElementsByTagName( 'IMG' ),
i = aImg.length;
while ( i-- ) {
validateImage( aImg[i] );
}
CODEPEN:
This has been frustrating me for years. My CSS fix sets a background image on the img. When a dynamic image src doesn't load to the foreground, a placeholder is visible on the img's bg. This works if your images have a default size (e.g. height, min-height, width and/or min-width).
You'll see the broken image icon but it's an improvement. Tested down to IE9 successfully. iOS Safari and Chrome don't even show a broken icon.
.dynamicContainer img {
background: url('/images/placeholder.png');
background-size: contain;
}
Add a little animation to give src time to load without a background flicker. Chrome fades in the background smoothly but desktop Safari doesn't.
.dynamicContainer img {
background: url('/images/placeholder.png');
background-size: contain;
animation: fadein 1s;
}
#keyframes fadein {
0% { opacity: 0.0; }
50% { opacity: 0.5; }
100% { opacity: 1.0; }
}
.dynamicContainer img {
background: url('https://picsum.photos/id/237/200');
background-size: contain;
animation: fadein 1s;
}
#keyframes fadein {
0% {
opacity: 0.0;
}
50% {
opacity: 0.5;
}
100% {
opacity: 1.0;
}
}
img {
/* must define dimensions */
width: 200px;
height: 200px;
min-width: 200px;
min-height: 200px;
/* hides broken text */
color: transparent;
/* optional css below here */
display: block;
border: .2em solid black;
border-radius: 1em;
margin: 1em;
}
<div class="dynamicContainer">
<img src="https://picsum.photos/200" alt="Found image" />
<img src="https://picsumx.photos/200" alt="Not found image" />
</div>
If you have inserted your img with innerHTML, like: $("div").innerHTML = <img src="wrong-uri">, you can load another image if it fails doing, e.g, this:
<script>
function imgError(img) {
img.error="";
img.src="valid-uri";
}
</script>
<img src="wrong-uri" onerror="javascript:imgError(this)">
Why is javascript: _needed? Because scripts injected into the DOM via script tags in innerHTML are not run at the time they are injected, so you have to be explicit.
Better call using
jQuery(window).load(function(){
$.imgReload();
});
Because using document.ready doesn't necessary imply that images are loaded, only the HTML. Thus, there is no need for a delayed call.
CoffeeScript variant:
I made it to fix an issue with Turbolinks that causes the .error() method to get raised in Firefox sometimes even though the image is really there.
$("img").error ->
e = $(#).get 0
$(#).hide() if !$.browser.msie && (typeof this.naturalWidth == "undefined" || this.naturalWidth == 0)
By using Prestaul's answer, I added some checks and I prefer to use the jQuery way.
<img src="image1.png" onerror="imgError(this,1);"/>
<img src="image2.png" onerror="imgError(this,2);"/>
function imgError(image, type) {
if (typeof jQuery !== 'undefined') {
var imgWidth=$(image).attr("width");
var imgHeight=$(image).attr("height");
// Type 1 puts a placeholder image
// Type 2 hides img tag
if (type == 1) {
if (typeof imgWidth !== 'undefined' && typeof imgHeight !== 'undefined') {
$(image).attr("src", "http://lorempixel.com/" + imgWidth + "/" + imgHeight + "/");
} else {
$(image).attr("src", "http://lorempixel.com/200/200/");
}
} else if (type == 2) {
$(image).hide();
}
}
return true;
}
I found this post while looking at this other SO post. Below is a copy of the answer I gave there.
I know this is an old thread, but React has become popular and, perhaps, someone using React will come here looking for an answer to the same problem.
So, if you are using React, you can do something like the below, which was an answer original provided by Ben Alpert of the React team here
getInitialState: function(event) {
return {image: "http://example.com/primary_image.jpg"};
},
handleError: function(event) {
this.setState({image: "http://example.com/failover_image.jpg"});
},
render: function() {
return (
<img onError={this.handleError} src={src} />;
);
}
I created a fiddle to replace the broken image using "onerror" event.
This may help you.
//the placeholder image url
var defaultUrl = "url('https://sadasd/image02.png')";
$('div').each(function(index, item) {
var currentUrl = $(item).css("background-image").replace(/^url\(['"](.+)['"]\)/, '$1');
$('<img>', {
src: currentUrl
}).on("error", function(e) {
$this = $(this);
$this.css({
"background-image": defaultUrl
})
e.target.remove()
}.bind(this))
})
Here is an example using the HTML5 Image object wrapped by JQuery. Call the load function for the primary image URL and if that load causes an error, replace the src attribute of the image with a backup URL.
function loadImageUseBackupUrlOnError(imgId, primaryUrl, backupUrl) {
var $img = $('#' + imgId);
$(new Image()).load().error(function() {
$img.attr('src', backupUrl);
}).attr('src', primaryUrl)
}
<img id="myImage" src="primary-image-url"/>
<script>
loadImageUseBackupUrlOnError('myImage','primary-image-url','backup-image-url');
</script>
Pure JS.
My task was: if image 'bl-once.png' is empty -> insert the first one (that hasn't 404 status) image from array list (in current dir):
<img src="http://localhost:63342/GetImage/bl-once.png" width="200" onerror="replaceEmptyImage.insertImg(this)">
Maybe it needs to be improved, but:
var srcToInsertArr = ['empty1.png', 'empty2.png', 'needed.png', 'notActual.png']; // try to insert one by one img from this array
var path;
var imgNotFounded = true; // to mark when success
var replaceEmptyImage = {
insertImg: function (elem) {
if (srcToInsertArr.length == 0) { // if there are no more src to try return
return "no-image.png";
}
if(!/undefined/.test(elem.src)) { // remember path
path = elem.src.split("/").slice(0, -1).join("/"); // "http://localhost:63342/GetImage"
}
var url = path + "/" + srcToInsertArr[0];
srcToInsertArr.splice(0, 1); // tried 1 src
if(imgNotFounded){ // while not success
replaceEmptyImage.getImg(url, path, elem); // CALL GET IMAGE
}
},
getImg: function (src, path, elem) { // GET IMAGE
if (src && path && elem) { // src = "http://localhost:63342/GetImage/needed.png"
var pathArr = src.split("/"); // ["http:", "", "localhost:63342", "GetImage", "needed.png"]
var name = pathArr[pathArr.length - 1]; // "needed.png"
xhr = new XMLHttpRequest();
xhr.open('GET', src, true);
xhr.send();
xhr.onreadystatechange = function () {
if (xhr.status == 200) {
elem.src = src; // insert correct src
imgNotFounded = false; // mark success
}
else {
console.log(name + " doesn't exist!");
elem.onerror();
}
}
}
}
};
So, it will insert correct 'needed.png' to my src or 'no-image.png' from current dir.
(window.jQuery || window.Zepto).fn.fallback = function (fallback) {
return this.one('error', function () {
var self = this;
this.src = (fallback || 'http://lorempixel.com/$width/$height').replace(
/\$(\w+)/g, function (m, t) { return self[t] || ''; }
);
});
};
You can pass a placeholder path and acces in it all properties from the failed image object via $*:
$('img').fallback('http://dummyimage.com/$widthx$height&text=$src');
http://jsfiddle.net/ARTsinn/Cu4Zn/
For React Developers:
<img
src={"https://urlto/yourimage.png"} // <--- If this image src fail to load, onError function will be called, where you can add placeholder image or any image you want to load
width={200}
alt={"Image"}
onError={(event) => {
event.target.onerror = "";
event.target.src = "anyplaceholderimageUrlorPath"
return true;
}}
/>
I am not sure if there is a better way, but I can think of a hack to get it - you could Ajax post to the img URL, and parse the response to see if the image actually came back. If it came back as a 404 or something, then swap out the img. Though I expect this to be quite slow.
I solved my problem with these two simple functions:
function imgExists(imgPath) {
var http = jQuery.ajax({
type:"HEAD",
url: imgPath,
async: false
});
return http.status != 404;
}
function handleImageError() {
var imgPath;
$('img').each(function() {
imgPath = $(this).attr('src');
if (!imgExists(imgPath)) {
$(this).attr('src', 'images/noimage.jpg');
}
});
}
jQuery 1.8
// If missing.png is missing, it is replaced by replacement.png
$( "img" )
.error(function() {
$( this ).attr( "src", "replacement.png" );
})
.attr( "src", "missing.png" );
jQuery 3
// If missing.png is missing, it is replaced by replacement.png
$( "img" )
.on("error", function() {
$( this ).attr( "src", "replacement.png" );
})
.attr( "src", "missing.png" );
reference
Sometimes using the error event is not feasible, e.g. because you're trying to do something on a page that’s already loaded, such as when you’re running code via the console, a bookmarklet, or a script loaded asynchronously. In that case, checking that img.naturalWidth and img.naturalHeight are 0 seems to do the trick.
For example, here's a snippet to reload all broken images from the console:
$$("img").forEach(img => {
if (!img.naturalWidth && !img.naturalHeight) {
img.src = img.src;
}
}
I think I have a more elegant way with event delegation and event capturing on window's error even when the backup image fail to load.
img {
width: 100px;
height: 100px;
}
<script>
window.addEventListener('error', windowErrorCb, {
capture: true
}, true)
function windowErrorCb(event) {
let target = event.target
let isImg = target.tagName.toLowerCase() === 'img'
if (isImg) {
imgErrorCb()
return
}
function imgErrorCb() {
let isImgErrorHandled = target.hasAttribute('data-src-error')
if (!isImgErrorHandled) {
target.setAttribute('data-src-error', 'handled')
target.src = 'backup.png'
} else {
//anything you want to do
console.log(target.alt, 'both origin and backup image fail to load!');
}
}
}
</script>
<img id="img" src="error1.png" alt="error1">
<img id="img" src="error2.png" alt="error2">
<img id="img" src="https://i.stack.imgur.com/ZXCE2.jpg" alt="avatar">
The point is :
Put the code in the head and executed as the first inline script. So, it will listen the errors happen after the script.
Use event capturing to catch the errors, especially for those events which don't bubble.
Use event delegation which avoids binding events on each image.
Give the error img element an attribute after giving them a backup.png to avoid disappearance of the backup.png and subsequent infinite loop like below:
img error->backup.png->error->backup.png->error->,,,,,
If the image cannot be loaded (for example, because it is not present at the supplied URL), image URL will be changed into default,
For more about .error()
$('img').on('error', function (e) {
$(this).attr('src', 'broken.png');
});
I got the same problem. This code works well on my case.
// Replace broken images by a default img
$('img').each(function(){
if($(this).attr('src') === ''){
this.src = '/default_feature_image.png';
}
});

Trying to reload Image variable until successful or a max amount of attempts is reached

I am trying to create a function that will recursively try to reload an image until it either is successful, or a maximum amount of attempts is reached. I have created this function, but it doesn't work (is it due to the fact that the reference to the image has changed?):
function reload (image, URL, maxAttempts)
{
image.onerror = image.onabort = null;
if (maxAttempts > 0)
{
var newImg = new Image ();
newImg.src = URL;
newImg.onerror = image.onabort = reload (image, URL, maxAttempts - 1);
newImg.onload = function () {
newImg.onerror = newImg.onabort = null;
image = newImg;
}
}
else
{
alert ("Error loading image " + URL); /* DEBUG */
}
}
Which is used in the following manner:
var globalTestImage = new Image ();
reload (globalTestImage, "testIMG.jpg", 4);
Rather than it attempting to load "testIMG.jpg" four times, and waiting in between attempts, it instead tries to load it twice, and regardless of whether it was successful the second time around it will display the error message.
What am I doing there? More precisely, why is it acting the way it is, rather than retrying to load the image 4 times?
(function ($) {
var retries = 5; //<--retries
$( document).ready(function(){
$('img').one('error', function() {
var $image = $(this);
$image.attr('alt', 'Still didn\'t load');
if (typeof $image !== 'undefined') {
if (typeof $image.attr('src') !== 'undefined') {
$image.attr('src', retryToLoadImage($image));
}
}
});
});
function retryToLoadImage($img) {
var $newImg = $('<img>');
var $src = ($img.attr('src')) || '';
$newImg.attr('src', $src);
$newImg.one('error', function() {
window.setTimeout(function(){
if (retries > 0) {
retries--;
retryToLoadImage($newImg);
}
}, 1000); //<-retry interval
});
$newImg.one('load', function() {
return $newImg.attr('src');
});
}
})(jQuery);
Some code I wrote for the same case a while ago. Hope it helps you!
In the end I solve this issue in a simple (if inelegant) way:
try
{
canvas.getContext("2d").drawImage (testImage, 0, 0);
backgroundLoaded = true;
}
catch (err)
{
testImage = new Image ();
testImage.src = "placeholder.jpg";
}
The idea is that if an image failed to load, it will fail when rendering it on the canvas, producing an error. When such an error happens, we can create a new image and try again.

How to put a default image if img tag is empty using jquery [duplicate]

I have a web page that includes a bunch of images. Sometimes the image isn't available, so a broken image is displayed in the client's browser.
How do I use jQuery to get the set of images, filter it to broken images then replace the src?
--I thought it would be easier to do this with jQuery, but it turned out much easier to just use a pure JavaScript solution, that is, the one provided by Prestaul.
Handle the onError event for the image to reassign its source using JavaScript:
function imgError(image) {
image.onerror = "";
image.src = "/images/noimage.gif";
return true;
}
<img src="image.png" onerror="imgError(this);"/>
Or without a JavaScript function:
<img src="image.png" onError="this.onerror=null;this.src='/images/noimage.gif';" />
The following compatibility table lists the browsers that support the error facility:
http://www.quirksmode.org/dom/events/error.html
I use the built in error handler:
$("img").error(function () {
$(this).unbind("error").attr("src", "broken.gif");
});
Edit: The error() method is deprecated in jquery 1.8 and higher. Instead, you should use .on("error") instead:
$("img").on("error", function () {
$(this).attr("src", "broken.gif");
});
In case someone like me, tries to attach the error event to a dynamic HTML img tag, I'd like to point out that, there is a catch:
Apparently img error events don't bubble in most browsers, contrary to what the standard says.
So, something like the following will not work:
$(document).on('error', 'img', function () { ... })
Hope this will be helpful to someone else. I wish I had seen this here in this thread. But, I didn't. So, I am adding it
Here is a standalone solution:
$(window).load(function() {
$('img').each(function() {
if ( !this.complete
|| typeof this.naturalWidth == "undefined"
|| this.naturalWidth == 0 ) {
// image was broken, replace with your new image
this.src = 'http://www.tranism.com/weblog/images/broken_ipod.gif';
}
});
});
I believe this is what you're after: jQuery.Preload
Here's the example code from the demo, you specify the loading and not found images and you're all set:
jQuery('#images img').preload({
placeholder:'placeholder.jpg',
notFound:'notfound.jpg'
});
$(window).bind('load', function() {
$('img').each(function() {
if( (typeof this.naturalWidth != "undefined" && this.naturalWidth == 0)
|| this.readyState == 'uninitialized' ) {
$(this).attr('src', 'missing.jpg');
}
});
});
Source: http://www.developria.com/2009/03/jquery-quickie---broken-images.html
While the OP was looking to replace the SRC, I'm sure many people hitting this question may only wish to hide the broken image, in which case this simple solution worked great for me.
Using Inline JavaScript:
<img src="img.jpg" onerror="this.style.display='none';" />
Using External JavaScript:
var images = document.querySelectorAll('img');
for (var i = 0; i < images.length; i++) {
images[i].onerror = function() {
this.style.display='none';
}
}
<img src='img.jpg' />
Using Modern External JavaScript:
document.querySelectorAll('img').forEach((img) => {
img.onerror = function() {
this.style.display = 'none';
}
});
<img src='img.jpg' />
See browser support for NodeList.forEach and arrow functions.
Here is a quick-and-dirty way to replace all the broken images, and there is no need to change the HTML code ;)
codepen example
$("img").each(function(){
var img = $(this);
var image = new Image();
image.src = $(img).attr("src");
var no_image = "https://dummyimage.com/100x100/7080b5/000000&text=No+image";
if (image.naturalWidth == 0 || image.readyState == 'uninitialized'){
$(img).unbind("error").attr("src", no_image).css({
height: $(img).css("height"),
width: $(img).css("width"),
});
}
});
This is a crappy technique, but it's pretty much guaranteed:
<img onerror="this.parentNode.removeChild(this);">
I couldn't find a script to suit my needs, so I made a recursive function to check for broken images and attempt to reload them every four seconds until they are fixed.
I limited it to 10 attempts as if it's not loaded by then the image might not be present on server and the function would enter an infinite loop. I am still testing though. Feel free to tweak it :)
var retries = 0;
$.imgReload = function() {
var loaded = 1;
$("img").each(function() {
if (!this.complete || typeof this.naturalWidth == "undefined" || this.naturalWidth == 0) {
var src = $(this).attr("src");
var date = new Date();
$(this).attr("src", src + "?v=" + date.getTime()); //slightly change url to prevent loading from cache
loaded =0;
}
});
retries +=1;
if (retries < 10) { // If after 10 retries error images are not fixed maybe because they
// are not present on server, the recursion will break the loop
if (loaded == 0) {
setTimeout('$.imgReload()',4000); // I think 4 seconds is enough to load a small image (<50k) from a slow server
}
// All images have been loaded
else {
// alert("images loaded");
}
}
// If error images cannot be loaded after 10 retries
else {
// alert("recursion exceeded");
}
}
jQuery(document).ready(function() {
setTimeout('$.imgReload()',5000);
});
You can use GitHub's own fetch for this:
Frontend: https://github.com/github/fetch
or for Backend, a Node.js version: https://github.com/bitinn/node-fetch
fetch(url)
.then(function(res) {
if (res.status == '200') {
return image;
} else {
return placeholder;
}
}
Edit: This method is going to replace XHR and supposedly already has been in Chrome. To anyone reading this in the future, you may not need the aforementioned library included.
This is JavaScript, should be cross browser compatible, and delivers without the ugly markup onerror="":
var sPathToDefaultImg = 'http://cdn.sstatic.net/stackexchange/img/logos/so/so-icon.png',
validateImage = function( domImg ) {
oImg = new Image();
oImg.onerror = function() {
domImg.src = sPathToDefaultImg;
};
oImg.src = domImg.src;
},
aImg = document.getElementsByTagName( 'IMG' ),
i = aImg.length;
while ( i-- ) {
validateImage( aImg[i] );
}
CODEPEN:
This has been frustrating me for years. My CSS fix sets a background image on the img. When a dynamic image src doesn't load to the foreground, a placeholder is visible on the img's bg. This works if your images have a default size (e.g. height, min-height, width and/or min-width).
You'll see the broken image icon but it's an improvement. Tested down to IE9 successfully. iOS Safari and Chrome don't even show a broken icon.
.dynamicContainer img {
background: url('/images/placeholder.png');
background-size: contain;
}
Add a little animation to give src time to load without a background flicker. Chrome fades in the background smoothly but desktop Safari doesn't.
.dynamicContainer img {
background: url('/images/placeholder.png');
background-size: contain;
animation: fadein 1s;
}
#keyframes fadein {
0% { opacity: 0.0; }
50% { opacity: 0.5; }
100% { opacity: 1.0; }
}
.dynamicContainer img {
background: url('https://picsum.photos/id/237/200');
background-size: contain;
animation: fadein 1s;
}
#keyframes fadein {
0% {
opacity: 0.0;
}
50% {
opacity: 0.5;
}
100% {
opacity: 1.0;
}
}
img {
/* must define dimensions */
width: 200px;
height: 200px;
min-width: 200px;
min-height: 200px;
/* hides broken text */
color: transparent;
/* optional css below here */
display: block;
border: .2em solid black;
border-radius: 1em;
margin: 1em;
}
<div class="dynamicContainer">
<img src="https://picsum.photos/200" alt="Found image" />
<img src="https://picsumx.photos/200" alt="Not found image" />
</div>
If you have inserted your img with innerHTML, like: $("div").innerHTML = <img src="wrong-uri">, you can load another image if it fails doing, e.g, this:
<script>
function imgError(img) {
img.error="";
img.src="valid-uri";
}
</script>
<img src="wrong-uri" onerror="javascript:imgError(this)">
Why is javascript: _needed? Because scripts injected into the DOM via script tags in innerHTML are not run at the time they are injected, so you have to be explicit.
Better call using
jQuery(window).load(function(){
$.imgReload();
});
Because using document.ready doesn't necessary imply that images are loaded, only the HTML. Thus, there is no need for a delayed call.
CoffeeScript variant:
I made it to fix an issue with Turbolinks that causes the .error() method to get raised in Firefox sometimes even though the image is really there.
$("img").error ->
e = $(#).get 0
$(#).hide() if !$.browser.msie && (typeof this.naturalWidth == "undefined" || this.naturalWidth == 0)
By using Prestaul's answer, I added some checks and I prefer to use the jQuery way.
<img src="image1.png" onerror="imgError(this,1);"/>
<img src="image2.png" onerror="imgError(this,2);"/>
function imgError(image, type) {
if (typeof jQuery !== 'undefined') {
var imgWidth=$(image).attr("width");
var imgHeight=$(image).attr("height");
// Type 1 puts a placeholder image
// Type 2 hides img tag
if (type == 1) {
if (typeof imgWidth !== 'undefined' && typeof imgHeight !== 'undefined') {
$(image).attr("src", "http://lorempixel.com/" + imgWidth + "/" + imgHeight + "/");
} else {
$(image).attr("src", "http://lorempixel.com/200/200/");
}
} else if (type == 2) {
$(image).hide();
}
}
return true;
}
I found this post while looking at this other SO post. Below is a copy of the answer I gave there.
I know this is an old thread, but React has become popular and, perhaps, someone using React will come here looking for an answer to the same problem.
So, if you are using React, you can do something like the below, which was an answer original provided by Ben Alpert of the React team here
getInitialState: function(event) {
return {image: "http://example.com/primary_image.jpg"};
},
handleError: function(event) {
this.setState({image: "http://example.com/failover_image.jpg"});
},
render: function() {
return (
<img onError={this.handleError} src={src} />;
);
}
I created a fiddle to replace the broken image using "onerror" event.
This may help you.
//the placeholder image url
var defaultUrl = "url('https://sadasd/image02.png')";
$('div').each(function(index, item) {
var currentUrl = $(item).css("background-image").replace(/^url\(['"](.+)['"]\)/, '$1');
$('<img>', {
src: currentUrl
}).on("error", function(e) {
$this = $(this);
$this.css({
"background-image": defaultUrl
})
e.target.remove()
}.bind(this))
})
Here is an example using the HTML5 Image object wrapped by JQuery. Call the load function for the primary image URL and if that load causes an error, replace the src attribute of the image with a backup URL.
function loadImageUseBackupUrlOnError(imgId, primaryUrl, backupUrl) {
var $img = $('#' + imgId);
$(new Image()).load().error(function() {
$img.attr('src', backupUrl);
}).attr('src', primaryUrl)
}
<img id="myImage" src="primary-image-url"/>
<script>
loadImageUseBackupUrlOnError('myImage','primary-image-url','backup-image-url');
</script>
Pure JS.
My task was: if image 'bl-once.png' is empty -> insert the first one (that hasn't 404 status) image from array list (in current dir):
<img src="http://localhost:63342/GetImage/bl-once.png" width="200" onerror="replaceEmptyImage.insertImg(this)">
Maybe it needs to be improved, but:
var srcToInsertArr = ['empty1.png', 'empty2.png', 'needed.png', 'notActual.png']; // try to insert one by one img from this array
var path;
var imgNotFounded = true; // to mark when success
var replaceEmptyImage = {
insertImg: function (elem) {
if (srcToInsertArr.length == 0) { // if there are no more src to try return
return "no-image.png";
}
if(!/undefined/.test(elem.src)) { // remember path
path = elem.src.split("/").slice(0, -1).join("/"); // "http://localhost:63342/GetImage"
}
var url = path + "/" + srcToInsertArr[0];
srcToInsertArr.splice(0, 1); // tried 1 src
if(imgNotFounded){ // while not success
replaceEmptyImage.getImg(url, path, elem); // CALL GET IMAGE
}
},
getImg: function (src, path, elem) { // GET IMAGE
if (src && path && elem) { // src = "http://localhost:63342/GetImage/needed.png"
var pathArr = src.split("/"); // ["http:", "", "localhost:63342", "GetImage", "needed.png"]
var name = pathArr[pathArr.length - 1]; // "needed.png"
xhr = new XMLHttpRequest();
xhr.open('GET', src, true);
xhr.send();
xhr.onreadystatechange = function () {
if (xhr.status == 200) {
elem.src = src; // insert correct src
imgNotFounded = false; // mark success
}
else {
console.log(name + " doesn't exist!");
elem.onerror();
}
}
}
}
};
So, it will insert correct 'needed.png' to my src or 'no-image.png' from current dir.
(window.jQuery || window.Zepto).fn.fallback = function (fallback) {
return this.one('error', function () {
var self = this;
this.src = (fallback || 'http://lorempixel.com/$width/$height').replace(
/\$(\w+)/g, function (m, t) { return self[t] || ''; }
);
});
};
You can pass a placeholder path and acces in it all properties from the failed image object via $*:
$('img').fallback('http://dummyimage.com/$widthx$height&text=$src');
http://jsfiddle.net/ARTsinn/Cu4Zn/
For React Developers:
<img
src={"https://urlto/yourimage.png"} // <--- If this image src fail to load, onError function will be called, where you can add placeholder image or any image you want to load
width={200}
alt={"Image"}
onError={(event) => {
event.target.onerror = "";
event.target.src = "anyplaceholderimageUrlorPath"
return true;
}}
/>
I am not sure if there is a better way, but I can think of a hack to get it - you could Ajax post to the img URL, and parse the response to see if the image actually came back. If it came back as a 404 or something, then swap out the img. Though I expect this to be quite slow.
I solved my problem with these two simple functions:
function imgExists(imgPath) {
var http = jQuery.ajax({
type:"HEAD",
url: imgPath,
async: false
});
return http.status != 404;
}
function handleImageError() {
var imgPath;
$('img').each(function() {
imgPath = $(this).attr('src');
if (!imgExists(imgPath)) {
$(this).attr('src', 'images/noimage.jpg');
}
});
}
jQuery 1.8
// If missing.png is missing, it is replaced by replacement.png
$( "img" )
.error(function() {
$( this ).attr( "src", "replacement.png" );
})
.attr( "src", "missing.png" );
jQuery 3
// If missing.png is missing, it is replaced by replacement.png
$( "img" )
.on("error", function() {
$( this ).attr( "src", "replacement.png" );
})
.attr( "src", "missing.png" );
reference
Sometimes using the error event is not feasible, e.g. because you're trying to do something on a page that’s already loaded, such as when you’re running code via the console, a bookmarklet, or a script loaded asynchronously. In that case, checking that img.naturalWidth and img.naturalHeight are 0 seems to do the trick.
For example, here's a snippet to reload all broken images from the console:
$$("img").forEach(img => {
if (!img.naturalWidth && !img.naturalHeight) {
img.src = img.src;
}
}
I think I have a more elegant way with event delegation and event capturing on window's error even when the backup image fail to load.
img {
width: 100px;
height: 100px;
}
<script>
window.addEventListener('error', windowErrorCb, {
capture: true
}, true)
function windowErrorCb(event) {
let target = event.target
let isImg = target.tagName.toLowerCase() === 'img'
if (isImg) {
imgErrorCb()
return
}
function imgErrorCb() {
let isImgErrorHandled = target.hasAttribute('data-src-error')
if (!isImgErrorHandled) {
target.setAttribute('data-src-error', 'handled')
target.src = 'backup.png'
} else {
//anything you want to do
console.log(target.alt, 'both origin and backup image fail to load!');
}
}
}
</script>
<img id="img" src="error1.png" alt="error1">
<img id="img" src="error2.png" alt="error2">
<img id="img" src="https://i.stack.imgur.com/ZXCE2.jpg" alt="avatar">
The point is :
Put the code in the head and executed as the first inline script. So, it will listen the errors happen after the script.
Use event capturing to catch the errors, especially for those events which don't bubble.
Use event delegation which avoids binding events on each image.
Give the error img element an attribute after giving them a backup.png to avoid disappearance of the backup.png and subsequent infinite loop like below:
img error->backup.png->error->backup.png->error->,,,,,
If the image cannot be loaded (for example, because it is not present at the supplied URL), image URL will be changed into default,
For more about .error()
$('img').on('error', function (e) {
$(this).attr('src', 'broken.png');
});
I got the same problem. This code works well on my case.
// Replace broken images by a default img
$('img').each(function(){
if($(this).attr('src') === ''){
this.src = '/default_feature_image.png';
}
});

JavaScript Image onload not called

I'm trying to draw an image on the Canvas in Javascript, but ofcourse I want to wait until the image is loaded. However, my onload function seems to be never called.
Here is what I've tried:
function GameObject(x, y)
{
this.x = x;
this.y = y;
this.image = {};
this.loaded = false;
this.load = function(filename)
{
this.image = new Image();
this.image.onload = function()
{
alert("image loaded");
this.loaded = true;
};
this.image.src = filename;
};
};
I'm calling the load function like this:
$( document ).ready(function()
{
main();
});
var player = new Player(0, 0);
function main()
{
player.load("images/player.png");
};
and Player inherits from GameObject.
When using FireBug, it looks like the image is loaded, however the alert "image loaded" is never shown and this.loaded remains false.
What could be wrong?
EDIT: The image is now loaded (there was an error in the path name), but this.loaded is never set to true, while the alert is called.
You should look for loaded field in player.image object.
In order to loaded be assigned to the player object you should rewrite part of your code like this:
this.load = function(filename)
{
var self = this;
this.image = new Image();
this.image.onload = function()
{
alert("image loaded");
self.loaded = true;
};
this.image.src = filename;
};
The problem is that when onload is called the context (to what this points) is the image object. So you have to save your initial context in the self.
you may think that it's a hard way but believe me it's not:
if you want to use jQuery load Event for images let me tell you a truth : "That Is a SHIT" so you should use :
.imagesLoaded()
but before using that you should first download it here
after downloading do these steps:
attach your .imagesLoaded() library js file into your first code as you did for main jQuery.js
write this code for the image you want to check if loaded or not:
$('#container').imagesLoaded()
.always( function( instance ) {
console.log('all images loaded');
})
.done( function( instance ) {
console.log('all images successfully loaded');
})
.fail( function() {
console.log('all images loaded, at least one is broken');
})
.progress( function( instance, image ) {
var result = image.isLoaded ? 'loaded' : 'broken';
console.log( 'image is ' + result + ' for ' + image.img.src );
});
put the address of you picture instead of #container in the code
ENJOY:))

How to create a JavaScript callback for knowing when an image is loaded?

I want to know when an image has finished loading. Is there a way to do it with a callback?
If not, is there a way to do it at all?
.complete + callback
This is a standards compliant method without extra dependencies, and waits no longer than necessary:
var img = document.querySelector('img')
function loaded() {
alert('loaded')
}
if (img.complete) {
loaded()
} else {
img.addEventListener('load', loaded)
img.addEventListener('error', function() {
alert('error')
})
}
Source: http://www.html5rocks.com/en/tutorials/es6/promises/
Image.onload() will often work.
To use it, you'll need to be sure to bind the event handler before you set the src attribute.
Related Links:
Mozilla on Image.onload()
Example Usage:
window.onload = function () {
var logo = document.getElementById('sologo');
logo.onload = function () {
alert ("The image has loaded!");
};
setTimeout(function(){
logo.src = 'https://edmullen.net/test/rc.jpg';
}, 5000);
};
<html>
<head>
<title>Image onload()</title>
</head>
<body>
<img src="#" alt="This image is going to load" id="sologo"/>
<script type="text/javascript">
</script>
</body>
</html>
You can use the .complete property of the Javascript image class.
I have an application where I store a number of Image objects in an array, that will be dynamically added to the screen, and as they're loading I write updates to another div on the page. Here's a code snippet:
var gAllImages = [];
function makeThumbDivs(thumbnailsBegin, thumbnailsEnd)
{
gAllImages = [];
for (var i = thumbnailsBegin; i < thumbnailsEnd; i++)
{
var theImage = new Image();
theImage.src = "thumbs/" + getFilename(globals.gAllPageGUIDs[i]);
gAllImages.push(theImage);
setTimeout('checkForAllImagesLoaded()', 5);
window.status="Creating thumbnail "+(i+1)+" of " + thumbnailsEnd;
// make a new div containing that image
makeASingleThumbDiv(globals.gAllPageGUIDs[i]);
}
}
function checkForAllImagesLoaded()
{
for (var i = 0; i < gAllImages.length; i++) {
if (!gAllImages[i].complete) {
var percentage = i * 100.0 / (gAllImages.length);
percentage = percentage.toFixed(0).toString() + ' %';
userMessagesController.setMessage("loading... " + percentage);
setTimeout('checkForAllImagesLoaded()', 20);
return;
}
}
userMessagesController.setMessage(globals.defaultTitle);
}
Life is too short for jquery.
function waitForImageToLoad(imageElement){
return new Promise(resolve=>{imageElement.onload = resolve})
}
var myImage = document.getElementById('myImage');
var newImageSrc = "https://pmchollywoodlife.files.wordpress.com/2011/12/justin-bieber-bio-photo1.jpg?w=620"
myImage.src = newImageSrc;
waitForImageToLoad(myImage).then(()=>{
// Image have loaded.
console.log('Loaded lol')
});
<img id="myImage" src="">
You could use the load()-event in jQuery but it won't always fire if the image is loaded from the browser cache. This plugin https://github.com/peol/jquery.imgloaded/raw/master/ahpi.imgload.js can be used to remedy that problem.
If the goal is to style the img after browser has rendered image, you should:
const img = new Image();
img.src = 'path/to/img.jpg';
img.decode().then(() => {
/* set styles */
/* add img to DOM */
});
because the browser first loads the compressed version of image, then decodes it, finally paints it. since there is no event for paint you should run your logic after browser has decoded the img tag.
Here is jQuery equivalent:
var $img = $('img');
if ($img.length > 0 && !$img.get(0).complete) {
$img.on('load', triggerAction);
}
function triggerAction() {
alert('img has been loaded');
}
Not suitable for 2008 when the question was asked, but these days this works well for me:
async function newImageSrc(src) {
// Get a reference to the image in whatever way suits.
let image = document.getElementById('image-id');
// Update the source.
img.src = src;
// Wait for it to load.
await new Promise((resolve) => { image.onload = resolve; });
// Done!
console.log('image loaded! do something...');
}
these functions will solve the problem, you need to implement the DrawThumbnails function and have a global variable to store the images. I love to get this to work with a class object that has the ThumbnailImageArray as a member variable, but am struggling!
called as in addThumbnailImages(10);
var ThumbnailImageArray = [];
function addThumbnailImages(MaxNumberOfImages)
{
var imgs = [];
for (var i=1; i<MaxNumberOfImages; i++)
{
imgs.push(i+".jpeg");
}
preloadimages(imgs).done(function (images){
var c=0;
for(var i=0; i<images.length; i++)
{
if(images[i].width >0)
{
if(c != i)
images[c] = images[i];
c++;
}
}
images.length = c;
DrawThumbnails();
});
}
function preloadimages(arr)
{
var loadedimages=0
var postaction=function(){}
var arr=(typeof arr!="object")? [arr] : arr
function imageloadpost()
{
loadedimages++;
if (loadedimages==arr.length)
{
postaction(ThumbnailImageArray); //call postaction and pass in newimages array as parameter
}
};
for (var i=0; i<arr.length; i++)
{
ThumbnailImageArray[i]=new Image();
ThumbnailImageArray[i].src=arr[i];
ThumbnailImageArray[i].onload=function(){ imageloadpost();};
ThumbnailImageArray[i].onerror=function(){ imageloadpost();};
}
//return blank object with done() method
//remember user defined callback functions to be called when images load
return { done:function(f){ postaction=f || postaction } };
}
This worked for me:
// Usage
let img = await image_on_load(parent_element_to_put_img, image_url);
img.hidden = true;
// Functions
async function image_on_load(parent, url) {
let img = element(parent, 'img');
img.src = url;
await new Promise((resolve, reject) => {
element_on(img, 'load', () => {
resolve();
});
element_on(img, 'error', () => {
reject();
});
});
return img;
}
function element(parent, tag_name, text = '') {
let result = document.createElement(tag_name);
element_child_append(parent, result);
element_html_inner(result, text);
return result;
}
function element_child_append(parent, result) {
parent.appendChild(result);
}
function element_html_inner(result, text) {
result.innerHTML = text;
}
function element_on(e, event, on_event) {
e.addEventListener(event, async () => {
await on_event();
});
}
If you are using React.js, you could do this:
render() {
// ...
<img
onLoad={() => this.onImgLoad({ item })}
onError={() => this.onImgLoad({ item })}
src={item.src} key={item.key}
ref={item.key} />
// ...
}
Where:
- onLoad (...) now will called with something like this:
{ src: "https://......png", key:"1" }
you can use this as "key" to know which images is loaded correctly and which not.
- onError(...) it is the same but for errors.
- the object "item" is something like this { key:"..", src:".."}
you can use to store the images' URL and key in order to use in a list of images.

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