How to create a csv file on the fly and return to download?

Question

Laravel

Good afternoon.
When you click on the button, the csv file should be downloaded.
I do it via ajax. What method should be done? GET or POST?
Here is the function in the controller that is being requested via ajax

public function uploadToFile() {
....
       $orders = Order::where($arFilter)->orderBy('id', 'desc')->get();

        header('Content-Description: File Transfer');
        header("Cache-Control: public");
        header('Content-Disposition: attachement;filename="test.csv";');
        header('Content-Type: application/csv; charset=UTF-8');

        $titles = array("id", "От куда", "Куда");

        ob_start();
        $df = fopen("php://output", 'w');
        fputcsv($df, $titles, ';');
        foreach ($orders as $k => $order) {
            $arTmp = array($k, $order->fromCity, $order->toCity);
            fputcsv($df, $arTmp, ';');
        }
        fclose($df);
        $str = ob_get_clean();
}

In $str I get the text display of the file.
How can I get it to download?

Answer 1

https://laravel.com/docs/5.8/responses#file-downloads

return response()->streamDownload(function () {
    echo $str;
}, 'test.csv');

Answer 2

Remove ob_start();and$str = ob_get_clean();

Answer 3

Here is a simple script: aceweb.ru/articles/php/export-csv.php