foreignvalidator.php

<?php
namespace Bitrix\Main\ORM\Fields\Validators;
 
use Bitrix\Main\ORM;
use Bitrix\Main\Localization\Loc;
 
Loc::loadMessages(__FILE__);
 
class ForeignValidator extends Validator
{
    protected $errorPhraseCode = 'MAIN_ENTITY_VALIDATOR_FOREIGN';
    protected $reference = null;
    protected $filter = null;
    const NOT_EXISTS = 'BX_FOREIGN_NOT_EXISTS';
 
    public function __construct(ORM\Fields\Field $reference, array $filter = array())
    {
        $this->reference = $reference;
        $this->filter = $filter;
        parent::__construct();
    }
 
    public function validate($value, $primary, array $row, ORM\Fields\Field $field)
    {
        $query = new ORM\Query\Query($this->reference->getEntity());
        $query->setFilter(array('='.$this->reference->getName() => $value) + $this->filter);
        $query->setLimit(1);
        $result = $query->exec();
 
        if($result->fetch())
        {
            return true;
        }
        return  new ORM\Fields\FieldError($field, $this->getErrorMessage($value, $field), self::NOT_EXISTS);
    }
}