.xlsx file response to download Excel file generated by PHPSpreadsheet (Symfony HttpFoundation)

XlsxResponse.php

<?php

declare(strict_types=1);

namespace App\HttpFoundation;

use PhpOffice\PhpSpreadsheet\Writer\Xlsx;
use Symfony\Component\HttpFoundation\Response;

/**
 * XlsxResponse represents an .xlsx file response.
 */
class XlsxResponse extends Response
{
    private string $excelContent;

    public function __construct(Xlsx $writer, string $fileName)
    {
        ob_start();
        $writer->save('php://output');
        $this->excelContent = ob_get_contents();
        ob_end_clean();

        parent::__construct(
            null,
            200,
            [
                'Content-Disposition' => "attachment; filename=\"{$fileName}\"",
                'Content-Type' => 'application/octet-stream; charset=utf-8'
            ]
        );
    }

    /**
     * {@inheritDoc}
     */
    public function sendContent(): static
    {
        echo $this->excelContent;

        return $this;
    }
}