elemententity.php

См. документацию.

<?php
 
namespace Bitrix\Iblock\ORM;
 
use Bitrix\Iblock\EO_Iblock;
use Bitrix\Iblock\Iblock;
use Bitrix\Main\ORM\Entity;
 

abstract class ElementEntity extends Entity
{
    protected $iblock;

    public function setIblock($iblock)
    {
        $this->iblock = $iblock;
 
        $this->getField('IBLOCK_ID')->configureDefaultValue(
            $iblock->getId()
        );
    }

    public function getIblock()
    {
        return $this->iblock;
    }
 
    abstract public function getSingleValueTableName();
 
    abstract public function getMultiValueTableName();
}