如何制作一个按钮，当你点击它时会下载一个excel文件(phpspreadsheet)

<button id="downloadBtn">下载Excel文件</button>

<script>
document.getElementById("downloadBtn").addEventListener("click", function() {
    // 在此处执行后续操作
});
</script>

composer require phpoffice/phpspreadsheet

<?php
require 'vendor/autoload.php'; // 导入PhpSpreadsheet库

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

// 创建Excel文件
$spreadsheet = new Spreadsheet();
$sheet = $spreadsheet->getActiveSheet();
$sheet->setCellValue('A1', 'Hello World !');

// 保存Excel文件
$writer = new Xlsx($spreadsheet);
$filename = 'example.xlsx';
$writer->save($filename);

// 提供下载链接
header('Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet');
header('Content-Disposition: attachment;filename="'. $filename .'"');
header('Cache-Control: max-age=0');
$writer->save("php://output");
exit;
?>