checkexists.php

См. документацию.

<?php
 
namespace Bitrix\Catalog\Controller;
 
use Bitrix\Main\Result;
 
trait CheckExists
{
    abstract protected function getEntityTable();
 
    protected function isExistsRow(int $id): bool
    {
        $entityTable = $this->getEntityTable();
 
        $row = $entityTable::getRow([
            'select' => [
                'ID',
            ],
            'filter' => [
                '=ID' => $id,
            ],
        ]);
 
        return !empty($row);
    }

    protected function exists($id)
    {
        $result = new Result();
 
        if (!$this->isExistsRow($id))
        {
            $result->addError($this->getErrorEntityNotExists());
        }
 
        return $result;
    }
}