FormTestCheckboxesRadiosForm.php

<?php

namespace Drupal\form_test\Form;

use Drupal\Core\Form\FormBase;
use Drupal\Core\Form\FormStateInterface;
use Symfony\Component\HttpFoundation\JsonResponse;

/**
 * Form constructor to test expansion of #type checkboxes and radios.
 *
 * @internal
 */
class FormTestCheckboxesRadiosForm extends FormBase {

  /**
   * {@inheritdoc}
   */
  public function getFormId() {
    return 'form_test_checkboxes_radios';
  }

  /**
   * {@inheritdoc}
   */
  public function buildForm(array $form, FormStateInterface $form_state, $customize = FALSE) {

    // Expand #type checkboxes, setting custom element properties for some but not
    // all options.
    $form['checkboxes'] = [
      '#type' => 'checkboxes',
      '#title' => 'Checkboxes',
      '#options' => [
        0 => 'Zero',
        'foo' => 'Foo',
        1 => 'One',
        'bar' => $this
          ->t('<em>Bar - checkboxes</em>'),
        '>' => "<em>Special Char</em><script>alert('checkboxes');</script>",
      ],
    ];
    if ($customize) {
      $form['checkboxes'] += [
        'foo' => [
          '#description' => 'Enable to foo.',
        ],
        1 => [
          '#weight' => 10,
        ],
      ];
    }

    // Expand #type radios, setting custom element properties for some but not
    // all options.
    $form['radios'] = [
      '#type' => 'radios',
      '#title' => 'Radios',
      '#options' => [
        0 => 'Zero',
        'foo' => 'Foo',
        1 => 'One',
        'bar' => '<em>Bar - radios</em>',
        '>' => "<em>Special Char</em><script>alert('radios');</script>",
      ],
    ];
    if ($customize) {
      $form['radios'] += [
        'foo' => [
          '#description' => 'Enable to foo.',
        ],
        1 => [
          '#weight' => 10,
        ],
      ];
    }
    $form['submit'] = [
      '#type' => 'submit',
      '#value' => 'Submit',
    ];
    return $form;
  }

  /**
   * {@inheritdoc}
   */
  public function submitForm(array &$form, FormStateInterface $form_state) {
    $form_state
      ->setResponse(new JsonResponse($form_state
      ->getValues()));
  }

}