userfieldassembler.php

<?php
 
namespace Bitrix\Main\Grid\Row\Assembler\Field;
 
use Bitrix\Main\Grid\Row\FieldAssembler;
use Bitrix\Main\UserTable;
use CSite;
use CUser;
 
class UserFieldAssembler extends FieldAssembler
{
    private array $userCache = [];
 
    protected function loadUserName(int $userId): string
    {
        $nameFormat = CSite::GetNameFormat();
 
        $row = UserTable::getRow([
            'select' => [
                'ID',
                'LOGIN',
                'NAME',
                'LAST_NAME',
                'SECOND_NAME',
                'EMAIL',
                'TITLE',
            ],
            'filter' => [
                '=ID' => $userId,
            ],
        ]);
        if ($row)
        {
            return CUser::FormatName($nameFormat, $row, true, true);
        }
 
        return '';
    }
 
    private function getUserName(int $userId): ?string
    {
        if (!isset($this->userCache[$userId]))
        {
            $this->userCache[$userId] = $this->loadUserName($userId);
        }
 
        return $this->userCache[$userId];
    }
 
    protected function prepareColumn($value)
    {
        if (isset($value) && is_numeric($value))
        {
            $value = (int)$value;
            if ($value > 0)
            {
                return $this->getUserName($value);
            }
        }
 
        return null;
    }
}