“Uncaught TypeError: a.indexOf is not a function” error when opening new foundation project

Question

I've created a new Foundation 5 project through bash, with foundation new my-project. When I open the index.html file in Chrome an Uncaught TypeError: a.indexOf is not a function error is shown in the console, originating in jquery.min.js:4.

I created the project following the steps on the foundation site, but I can't seem to get rid of this error. Foundation and jQuery look like they are included and linked up correctly in the index.html file, and the linked app.js file is including $(document).foundation();

Does anyone know what is causing this error? and what a solution might be?

Answer 1

This error might be caused by jquery event aliases like .load, .unload or .error deprecated since jQuery 1.8. Look for these aliases in your code and replace them with .on() to register listeners instead. Example:

$(window).load(function(){...});

becomes:

$(window).on('load', function(){ ...});

Answer 2

This error is often caused by incompatible jQuery versions. I encountered the same error with a foundation 6 repository. My repository was using jQuery 3, but foundation requires an earlier version. I then changed it and it worked.

If you look at the version of jQuery required by the foundation 5 dependencies it states "jquery": "~2.1.0".

Can you confirm that you are loading the correct version of jQuery?

I hope this helps.

Answer 3

I faced this issue too. I was using jquery.poptrox.min.js for image popping and zooming and I received an error which says:

“Uncaught TypeError: a.indexOf is not a function” error.

This is because this is was not supported in the 3.3.1/jquery.min.js so a simple fix to this is to change it to an old version 2.1.0/jquery.min.js.

This way I was able to fix it for me.

Answer 4

One of the possible reasons is when you load jQuery TWICE ,like:

<script src='..../jquery.js'></script>
....
....
....
....
....
<script src='......./jquery.js'></script>

So, check your source code and remove duplicate jQuery load.

Answer 5

Please add below jQuery Migrate Plugin

<script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
<script src="https://code.jquery.com/jquery-migrate-1.4.1.min.js"></script>

Answer 6

I'm using jQuery 3.3.1 and I received the same error, in my case, the URL was an Object vs a string.

What happened was, that I took URL = window.location - which returned an object. Once I've changed it into window.location.href - it worked w/o the e.indexOf error.

Answer 7

I solved this by installing the correct version of Jquery that my project required using npm