Path: csiph.com!3.eu.feeder.erje.net!feeder.erje.net!news.mb-net.net!open-news-network.org!.POSTED.120.232.197.178.dynamic.wless.lssmb00p-cgnat.res.cust.swisscom.ch!not-for-mail
From: Thomas 'PointedEars' Lahn <PointedEars@web.de>
Newsgroups: comp.lang.javascript
Subject: Re: missing image error
Date: Wed, 05 Aug 2020 08:44:44 +0200
Organization: PointedEars Software (PES)
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Andrew Poulos wrote:

> let img = new Image();
> 
> img.src = 'images/' + name + '.jpg';
> img.setAttribute("onerror", "this.onerror=null;
  ^^^^^^^^^^^^^^^^^^^^              ^^^^^^^
> this.src='images/imagenotfound.png'");

Yuck.  

  img.onerror = function () {
    this.onerror = null;
    this.src = 'images/imagenotfound.png';
  };

Obviously the compatibility of this is at least as good as the compatibility 
of the original code.

However, for this to work reliably, as always, the event listener has to be 
defined *before* the property is changed that can fire the event:

  img.onerror = …;
  img.src = 'images/' + name + '.jpg';

> Is there a way to trap the 404 so it doesn't show in the console?

Unlikely.
 
> Or is there some other way I can try to get the image and thereby be
> able to trap the 404?

XMLHttpRequest/Fetch API.

-- 
PointedEars
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