How to write a handler for 1C-Bitrix?

Question

1C-Bitrix

Good day. It is
necessary to write a handler that, when importing goods, will check one custom property and change the root section using it
. we get all the goods from the unloading
-> section 1 -> section 2 -> element whose property = male
we enter it into the Bitrix database as
male -> section 1 -> section 2 -> element
Can someone tell me? I'm only learning, I ran into handlers for the second time

Answer 1

There are events before adding \ changing an element.

<?
// файл /bitrix/php_interface/init.php
// регистрируем обработчик
AddEventHandler("iblock", "OnBeforeIBlockElementAdd", Array("MyClass", "OnBeforeIBlockElementAddHandler"));

class MyClass
{
    // создаем обработчик события "OnBeforeIBlockElementAdd"
    function OnBeforeIBlockElementAddHandler(&$arFields)
    {
        if(strlen($arFields["CODE"])<=0)
        {
            global $APPLICATION;
            $APPLICATION->throwException("Введите символьный код.");
            return false;
        }
    }
}
?>

Well, for the update, you also need to issue

Answer 2

>> will check one custom property and change the root section based on it.
If you do this, then other "non-male" products can get into men's products.
It's easier to initially create the desired directory structure, and then bind them to the appropriate directories using certain attributes.