Symfony - how to create a pdf with some data selected by checkbox

Question

I have a page with a list of products and the detail. In the detail I have a button to generate a PDF file (works with KnpSnappy Bundle) of the product.

Now I want on the list page, to select the products with checkbox and create one pdf with all products selected but I don't really know how can I do that

I started with the integration of checkbox with the id of the product as the value and I made a button to send theses values to my controller with a new route

In my controller, I don't see how can I configure my new route and what could be my next step to generate the pdf with all of theses data

there is some code :

list view :

{{ form(form) }}

{%  for annonce in annonces %}
    {{ annonce._source.titre }}
    {{ annonce._source.reference }}
    <input type="checkbox" name="checkbox[]" value="{{annonce._id}}" multiple/>
{% endfor %}

<input type="submit" value="export" name="test" href="{{ path('annonce_pdf_multiple') }}">

{{ form_end(form) }}

Controller :

    /**
     * @Route("/", name="annonce_search", methods="GET|POST")
     * @Route("/", name="annonce_pdf_multiple", methods="POST") (it's my new route, should I add ids ?)
     */
    public function search(Request $request)
    {
      $select = $request->get('checkbox');
    }

if it can help there is the part code of how I generate one PDF to the show page :

show :

{{ annonce.ville.nom }}
{{ annonce.ville.codePostal }}
{{ SomeOtherData }}

//link to generate the pdf 
<a  href="{{ path('annonce_pdf', {'id': annonce.id}) }}">

controller :

 /**
     * @Route("/annonce/{id}/pdf", name="annonce_pdf", methods="GET")
     * @Route("/annonce/{id}/pdf/contact", name="annonce_pdf_contact", methods="GET", defaults={"contact": true})
     */
    public function pdf(Security $security, Annonce $annonce, bool $contact = false): Response
    {

            $filePath = $this->pdfService->pdfAnnonce($annonce, $contact);
            $response = new BinaryFileResponse($filePath);
//            $response->setContentDisposition(ResponseHeaderBag::DISPOSITION_ATTACHMENT);
            return $response;
        }

    }

The function pdfAnnonce() :

public function pdfAnnonce(Annonce $annonce, bool $contact = false) {
$filepath = $this->root.$this->directory.md5($annonce->getId()).'.pdf';

$this->pdf->generateFromHtml(
    $this->templating->render('@themes/'.$annonce->getWebsite()->toElasticaIndex().'/front/annonce/show.pdf.twig', [
        'annonce' => $annonce,
        'root' => $this->root,
        'contact' => $contact
    ]),
    $filepath,
    $options,
    true
);
return $filepath;

}

thanks you in advance