sectioncountfieldassembler.php

<?php
 
namespace Bitrix\Iblock\Grid\Row\Assembler;
 
use Bitrix\Iblock\Grid\RowType;
use Bitrix\Main\Grid\Row\FieldAssembler;
use CIBlockSection;
 
final class SectionCountFieldAssembler extends FieldAssembler
{
    private int $iblockId;
 
    public function __construct(int $iblockId)
    {
        parent::__construct([
            'SECTION_CNT',
        ]);
 
        $this->iblockId = $iblockId;
    }
 
    protected function prepareRow(array $row): array
    {
        $value = '';
 
        $id = (int)($row['data']['ID'] ?? 0);
        $rowType = $row['data']['ROW_TYPE'] ?? null;
        if ($id > 0 && $rowType === RowType::SECTION)
        {
            $value = CIBlockSection::GetCount([
                'IBLOCK_ID' => $this->iblockId,
                'SECTION_ID' => $id,
            ]);
        }
 
        $row['columns'] ??= [];
        $row['columns']['SECTION_CNT'] = $value;
 
        return $row;
    }
}