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Detecting a image 404 in javascript

Image
By User


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.


Source: Tips4all, CCNA FINAL EXAM
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Comments

  1. UserMay 13, 2012 at 8:24 AM

    Handle the <img> element's onerror event.

    ReplyDelete
  2. UserMay 13, 2012 at 8:24 AM

    This site details how to do it.

    Detecting Broken Images in JavaScript

    ReplyDelete

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