How to calculate the value of fields from properties when adding a new product?

Question

1C-Bitrix

Good afternoon!

Please advise. There is an infoblock "Catalogue" with ID 7. All goods are simple, without trade offers. There are properties length (width) and width (height). When adding a new product, the price must be calculated as follows:

Price = Width X Length X 130.

The price value must be written to the item. If the price is set manually, then the code should not be executed, the new price should not be written to the element.

If the price is not filled in and is recorded through the calculation according to the above formula, then the element should be deactivated.

Please let me know how this is done. I found the documentation https://dev.1c-bitrix.ru/api_help/iblock/events/on... - but I can't understand, a specific infoblock is not specified in the examples, there is no example with getting properties.