How is the form for adding an element processed in Bitrix and how to intercept it?

Question

1C-Bitrix

Description:
Wrote a template for the iblock.element.add.form component
But there are 2 nuances:
1. when adding an element with a name that already exists, it displays an error that the character code is the same (it is formed via js by the BX.translit function) .
2. when adding an element, it is necessary that parameters be added to the trade catalog for this element.
I see the solution as follows:
you need to write some kind of handler that will be processed after pressing "save", which will add an entry for the trade catalog and check the symbolic code for the presence of a similar one, and, if necessary, add numbering.
this handler must be between form submission and processing.
Tell me how to do it easier, preferably without ajax.

Answer 1

OnBeforeIBlockElementAdd