patashnik

<form method="post">
    <div>
        <label>First <input type="radio" name="choice" value="1" /></label>
        <input type="text" name="first_text" />
    </div>
    <div>
        <label>Second <input type="radio" name="choice" value="2" /></label>
        <input type="text" name="second_text" />
    </div>
</form>

patashnik

<?php

public function someAction()
{
    $factory = $this->get('form.factory');
    $form = $factory->create(new ExperimentalForm(), 'form');
    $request = $this->get('request');

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