Last Updated: 09 Sep 2020 10:48 by ADMIN
Angie Simants
Created on: 02 Sep 2020 14:40
Category: Ajax
Type: Bug Report
Error in IE: Unable to get property 'className' thrown an ajax request handler when referencing control

We have code for our ajaxified submit forms to disable the submit button on request start and re-enabled it on request end. This used to work, but when we upgraded to the latest build (2020.2.617), setting the disabled property to false now throws an error in IE from the WebResource.axd file (does not appear to have a problem in Firefox). The attached demo project shows exactly where the error occurs. Just click the Search button.

Attached picture shows an example of the error message thrown. The error does not appear to be with our javascript code itself; all the variables are populated and valid. It looks like something is getting triggered in the WebResource code when we set the disabled property to false and that is where the break is occurring.


Attached Files:
Attila Antal
Posted on: 09 Sep 2020 10:48

Hi Angie,

Thank you for sharing the project.

Before we assume it is a bug, I would like to point out that the current configuration is using Nested AJAX which is not supported and we have that mentioned in the Controls Wrapped in AjaxPanel and Added to AjaxManager Settings and Understanding AJAX Controls articles. This is one of the main reasons the application would fail. 

To fix this problem, please eliminate the nested AJAX and try to avoid nesting them in the future.

Kind regards,
Attila Antal
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Angie Simants
Posted on: 03 Sep 2020 17:45
Fyi, we were able to find a workaround by wrapping the offending .disabled = false line in a try/catch. The thrown javascript error appears to occur after actually setting the button's disabled property, so that appears to work well enough.