Symfony / Twig：表单小部件的内部ID？

Question

I've to modify the radio_widget and would like to give the <label> and <input> the same ID, which should be unique for each pair.

Currently I'm using random(), but I'd prefer an internal counter, something like {{loop.index}} (Twig: for), to avoid conflicts.

{% block radio_widget -%}
    {% set id = random() %}
    <div class="radio">
        <label for="radio_{{ id }}">Label for {{ id }}</label>
        <input type="radio" id="radio_{{ id }}" {# ...#}/>
    </div>
{%- endblock radio_widget %}

Does anyone know a better solution?

Thanks in advance!

Answer 1

For every form-widget there already exists a pre-calculated unique id.

See: \Symfony\Component\Form\Extension\Core\Type\BaseType::buildView

In twig this ID is accessible through {{ form.vars.id }}.

In essence the id is just a concatenation of the nested form-type names.

---

Note that form.vars in general contains all the useful stuff you'd need to do form-customization. It's also the place to put custom values when using FormTypeInterface::buildView or FormTypeInterface::finishView to transport data to the form rendering.