class FormErrorHandler
Same name in this branch
- 10 core/modules/inline_form_errors/src/FormErrorHandler.php \Drupal\inline_form_errors\FormErrorHandler
Same name in other branches
- 9 core/modules/inline_form_errors/src/FormErrorHandler.php \Drupal\inline_form_errors\FormErrorHandler
- 9 core/lib/Drupal/Core/Form/FormErrorHandler.php \Drupal\Core\Form\FormErrorHandler
- 8.9.x core/modules/inline_form_errors/src/FormErrorHandler.php \Drupal\inline_form_errors\FormErrorHandler
- 8.9.x core/lib/Drupal/Core/Form/FormErrorHandler.php \Drupal\Core\Form\FormErrorHandler
- 11.x core/modules/inline_form_errors/src/FormErrorHandler.php \Drupal\inline_form_errors\FormErrorHandler
- 11.x core/lib/Drupal/Core/Form/FormErrorHandler.php \Drupal\Core\Form\FormErrorHandler
Handles form errors.
Hierarchy
- class \Drupal\Core\Form\FormErrorHandler implements \Drupal\Core\Form\FormErrorHandlerInterface uses \Drupal\Core\Messenger\MessengerTrait
Expanded class hierarchy of FormErrorHandler
1 file declares its use of FormErrorHandler
- FormErrorHandler.php in core/
modules/ inline_form_errors/ src/ FormErrorHandler.php
1 string reference to 'FormErrorHandler'
- core.services.yml in core/
core.services.yml - core/core.services.yml
1 service uses FormErrorHandler
File
-
core/
lib/ Drupal/ Core/ Form/ FormErrorHandler.php, line 12
Namespace
Drupal\Core\FormView source
class FormErrorHandler implements FormErrorHandlerInterface {
use MessengerTrait;
/**
* {@inheritdoc}
*/
public function handleFormErrors(array &$form, FormStateInterface $form_state) {
// After validation check if there are errors.
if ($form_state->getErrors()) {
// Display error messages for each element.
$this->displayErrorMessages($form, $form_state);
// Loop through and assign each element its errors.
$this->setElementErrorsFromFormState($form, $form_state);
}
return $this;
}
/**
* Loops through and displays all form errors.
*
* @param array $form
* An associative array containing the structure of the form.
* @param \Drupal\Core\Form\FormStateInterface $form_state
* The current state of the form.
*/
protected function displayErrorMessages(array $form, FormStateInterface $form_state) {
$errors = $form_state->getErrors();
// Loop through all form errors and set an error message.
foreach ($errors as $error) {
$this->messenger()
->addMessage($error, 'error');
}
}
/**
* Stores errors and a list of child element errors directly on each element.
*
* Grouping elements like containers, details, fieldgroups and fieldsets may
* need error info from their child elements to be able to accessibly show
* form error messages to a user. For example, a details element should be
* opened when child elements have errors.
*
* Grouping example:
* Assume you have a 'street' element somewhere in a form, which is displayed
* in a details element 'address'. It might be:
*
* @code
* $form['street'] = [
* '#type' => 'textfield',
* '#title' => $this->t('Street'),
* '#group' => 'address',
* '#required' => TRUE,
* ];
* $form['address'] = [
* '#type' => 'details',
* '#title' => $this->t('Address'),
* ];
* @endcode
*
* When submitting an empty street field, the generated error is available to
* the different render elements like so:
* @code
* // The street textfield element.
* $element = [
* '#errors' => {Drupal\Core\StringTranslation\TranslatableMarkup},
* '#children_errors' => [],
* ];
* // The address detail element.
* $element = [
* '#errors' => null,
* '#children_errors' => [
* 'street' => {Drupal\Core\StringTranslation\TranslatableMarkup}
* ],
* ];
* @endcode
*
* The list of child element errors of an element is an associative array. A
* child element error is keyed with the #array_parents value of the
* respective element. The key is formed by imploding this value with '][' as
* glue. For example, a value ['contact_info', 'name'] becomes
* 'contact_info][name'.
*
* @param array $form
* An associative array containing a reference to the complete structure of
* the form.
* @param \Drupal\Core\Form\FormStateInterface $form_state
* The current state of the form.
* @param array $elements
* An associative array containing the part of the form structure that will
* be processed while traversing up the tree. For recursion only; leave
* empty when calling this method.
*/
protected function setElementErrorsFromFormState(array &$form, FormStateInterface $form_state, array &$elements = []) {
// At the start of traversing up the form tree set the to be processed
// elements to the complete form structure by reference so that we can
// modify the original form. When processing grouped elements a reference to
// the complete form is needed.
if (empty($elements)) {
// cspell:disable-next-line
// phpcs:ignore DrupalPractice.CodeAnalysis.VariableAnalysis.VariableRedeclaration
$elements =& $form;
}
// Recurse through all element children.
foreach (Element::children($elements) as $key) {
if (!empty($elements[$key])) {
// Get the child by reference so that we can update the original form.
$child =& $elements[$key];
// Call self to traverse up the form tree. The current element's child
// contains the next elements to be processed.
$this->setElementErrorsFromFormState($form, $form_state, $child);
$children_errors = [];
// Inherit all recorded "children errors" of the direct child.
if (!empty($child['#children_errors'])) {
$children_errors = $child['#children_errors'];
}
// Additionally store the errors of the direct child itself, keyed by
// its parent elements structure.
if (!empty($child['#errors'])) {
$child_parents = implode('][', $child['#array_parents']);
$children_errors[$child_parents] = $child['#errors'];
}
if (!empty($elements['#children_errors'])) {
$elements['#children_errors'] += $children_errors;
}
else {
$elements['#children_errors'] = $children_errors;
}
// If this direct child belongs to a group populate the grouping element
// with the children errors.
if (!empty($child['#group'])) {
$parents = explode('][', $child['#group']);
$group_element = NestedArray::getValue($form, $parents);
if (isset($group_element['#children_errors'])) {
$group_element['#children_errors'] = $group_element['#children_errors'] + $children_errors;
}
else {
$group_element['#children_errors'] = $children_errors;
}
NestedArray::setValue($form, $parents, $group_element);
}
}
}
// Store the errors for this element on the element directly.
$elements['#errors'] = $form_state->getError($elements);
}
}
Members
Title Sort descending | Modifiers | Object type | Summary | Overrides |
---|---|---|---|---|
FormErrorHandler::displayErrorMessages | protected | function | Loops through and displays all form errors. | 1 |
FormErrorHandler::handleFormErrors | public | function | ||
FormErrorHandler::setElementErrorsFromFormState | protected | function | Stores errors and a list of child element errors directly on each element. | |
MessengerTrait::$messenger | protected | property | The messenger. | 16 |
MessengerTrait::messenger | public | function | Gets the messenger. | 16 |
MessengerTrait::setMessenger | public | function | Sets the messenger. |
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