What is the easiest way to request an internal php function using ajax?

Question

JavaScript

Good afternoon!
The essence of the problem is this: there is CMS NetCat, there is a catalog page in the online store. On this page, a function is called from the NetCat API that generates filters for products in the right place in the layout:

<?= $netshop->filter->make_form() ?>

After processing, a post form with an empty action is generated. Individual values, arrays and other data for its construction are processed in a specific php file, but the final result is output by the system core. However, you can add an id or change the structure of the form as needed.

The task is to make this object dynamic, working without reloading the page or clicking the "Apply" button, and all this with the help of AJAX.

My knowledge of AJAX tends to zero and it is desirable to get the simplest way that would be clear to me.

Answer 1

It doesn't matter how and how it is displayed. Is it important where to send the request? If you know, then look at any example of an ajax request, catch a button click, collect data from the form and send it to the required php file.