Spreadsheets, driven by code.

<?php

require 'vendor/autoload.php';

use PhpOffice\PhpSpreadsheet\Spreadsheet;
use PhpOffice\PhpSpreadsheet\RichText\RichText;
use PhpOffice\PhpSpreadsheet\Style\Color;
use PhpOffice\PhpSpreadsheet\Writer\Xlsx;

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

// Build the rich-text value out of separate runs.
$rich = new RichText();
$rich->createText('Order #1024 ');

$overdue = $rich->createTextRun('OVERDUE');
$overdue->getFont()->setBold(true);
$overdue->getFont()->setColor(new Color(Color::COLOR_RED));

$rich->createText(' — pay within 14 days');

// Drop the whole RichText object into one cell.
$worksheet->setCellValue('A1', $rich);

$writer = new Xlsx($spreadsheet);
$writer->save('rich-text.xlsx');

echo "Wrote rich-text.xlsx\n";