Spreadsheets, driven by code.

<?php

require 'vendor/autoload.php';

use \PhpOffice\PhpSpreadsheet\Spreadsheet;
use \PhpOffice\PhpSpreadsheet\Writer\Xlsx;

$spreadsheet = new Spreadsheet();
$worksheet = $spreadsheet->getActiveSheet();

$worksheet->fromArray([
    ['id', 'name', 'email'],
    [1, 'John Doe', 'john@example.com'],
    [2, 'Jane Roe', 'jane@example.com'],
    [3, 'Sam Poe', 'sam@example.com'],
], null, 'A1');

$filename = 'users.xlsx';

header('Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet');
header('Content-Disposition: attachment; filename="' . $filename . '"');
header('Cache-Control: max-age=0');

while (ob_get_level() > 0) {
    ob_end_clean();
}

$writer = new Xlsx($spreadsheet);
$writer->save('php://output');

exit;