Symfony2: The CSRF token is invalid. Please try to resubmit the form

Question

I have a form wher I have to fill in some information in a field. Even if I put something inside, I am getting the error:

The CSRF token is invalid. Please t         


        

Answer 1

Send a serialized form using the serialize jQuery method:

$form.submit(function (e) {
    e.preventDefault();

    $this = $(this);
    $.post($this.attr('action'), $this.serialize(), function (response) {
        // handle the response here
    });
});

This way Symfony will handle the submit request as a normal request — you don't have to do anything special to handle an Ajax form submission. All you'll need to do is to return a JsonResponse — if you need it, of course.

Here is an example of handling the form — adapt it to your needs:

if ('POST' === $request->getMethod()) {
    $form->bind($request);

    if ($form->isValid()) {
        // do something here — like persisting or updating an entity

        return new JsonResponse([
            'success' => true,
        ]);
    }

    return new JsonResponse([
        'success' => false,
        'form' => $this->render($pathToTheTemplateHere, [
            'form' => $form,
        ],
    ]);
}

The other way would be to use different templates: form.json.twig and form.html.twig — read the docs for details.