How to make a letter with an invoice for payment in pdf on the site?

Question

PHP

I want to send a letter to buyers with an invoice with which they can go to the bank to pay

Answer 1

In Bitrix, in the Sale module, there is a CSalePdf class for working with PDF, it is used by system payment services.
An example of use and implementation can be found in the sources of the "Account (bill)" service. The source
is here bitrix\modules\sale\handlers\paysystem\bill\template\template_pdf.php