No route found for "GET symfony 4 - symfony

Question

I create a blog controller and the routes in the controller and the templates that correspond to it. but I get an error : No route found for "GET /blog/modifier/6". error
here is the function in the controller
note:it works in the backoffice
/**
* #Route("/modifier/{id}", name="modifier_posts", methods={"GET","POST"})
*/
public function modifierpost(Request $request, Posts $post, $id): Response
{
$post= $this->getDoctrine()->getRepository(Posts::class)->find($id);
$em= $this->getDoctrine()->getManager();
$form = $this->createForm(PostType::class, $post);
$form->handleRequest($request);
if ($form->isSubmitted() && $form->isValid()) {
$em= $this->getDoctrine()->getManager()->flush();
return $this->redirectToRoute('list_posts');
}
return $this->render('blog/modifierpost.html.twig', [
'form' => $form->createView()
]);
}
and the modifierpost.html.twig
{% extends 'base-front.html.twig' %}
{% block body %}
<div class="col-12 grid-margin stretch-card">
<div class="card">
<div class="card-body"><br><br><br><br>
"><i class="mdi mdi-arrow-left"></i></a>Mettre à jour d'un post</h4><br>
<div class="form-group">
{{ form_start(form) }}
{{ form_widget(form) }}
{{ form_end(form) }}
<button class="text-danger" style="font-size: 14px;background:none; border:none;margin:0;padding:0;cursor: pointer;text-decoration: underline red;" class="btn" type="submit"><i class="mdi mdi-delete"></i></button>
</div>
</div>
</div>
</div>
</div>
{% endblock %}
the error

Answer 1

You should use the ParamConverter. Make sure that you have a Post with the id equals to 6. And make sure that you have #Route("/blog") at the top of your controller class
/**
* #Route("/modifier/{id}", name="modifier_posts", methods={"GET","POST"})
**/
public function modifierpost(Request $request, Posts $post): Response
{
$form = $this->createForm(PostType::class, $post);
$form->handleRequest($request);
if ($form->isSubmitted() && $form->isValid()) {
$this->getDoctrine()->getManager()->flush();
return $this->redirectToRoute('list_posts');
}
return $this->render('blog/modifierpost.html.twig', [
'form' => $form->createView()
]);
}