function _form_validate in Drupal 7
Same name and namespace in other branches
- 4 includes/form.inc \_form_validate()
- 5 includes/form.inc \_form_validate()
- 6 includes/form.inc \_form_validate()
Performs validation on form elements.
First ensures required fields are completed, #maxlength is not exceeded, and selected options were in the list of options given to the user. Then calls user-defined validators.
Parameters
$elements: An associative array containing the structure of the form.
$form_state: A keyed array containing the current state of the form. The current user-submitted data is stored in $form_state['values'], though form validation functions are passed an explicit copy of the values for the sake of simplicity. Validation handlers can also $form_state to pass information on to submit handlers. For example: $form_state['data_for_submission'] = $data; This technique is useful when validation requires file parsing, web service requests, or other expensive requests that should not be repeated in the submission step.
$form_id: A unique string identifying the form for validation, submission, theming, and hook_form_alter functions.
Related topics
1 call to _form_validate()
- drupal_validate_form in includes/
form.inc - Validates user-submitted form data in the $form_state array.
File
- includes/
form.inc, line 1348 - Functions for form and batch generation and processing.
Code
function _form_validate(&$elements, &$form_state, $form_id = NULL) {
// Also used in the installer, pre-database setup.
$t = get_t();
// Recurse through all children.
foreach (element_children($elements) as $key) {
if (isset($elements[$key]) && $elements[$key]) {
_form_validate($elements[$key], $form_state);
}
}
// Validate the current input.
if (!isset($elements['#validated']) || !$elements['#validated']) {
// The following errors are always shown.
if (isset($elements['#needs_validation'])) {
// Verify that the value is not longer than #maxlength.
if (isset($elements['#maxlength']) && (isset($elements['#value']) && !is_scalar($elements['#value']))) {
form_error($elements, $t('An illegal value has been detected. Please contact the site administrator.'));
}
elseif (isset($elements['#maxlength']) && drupal_strlen($elements['#value']) > $elements['#maxlength']) {
form_error($elements, $t('!name cannot be longer than %max characters but is currently %length characters long.', array(
'!name' => empty($elements['#title']) ? $elements['#parents'][0] : $elements['#title'],
'%max' => $elements['#maxlength'],
'%length' => drupal_strlen($elements['#value']),
)));
}
if (isset($elements['#options']) && isset($elements['#value'])) {
if ($elements['#type'] == 'select') {
$options = form_options_flatten($elements['#options']);
}
else {
$options = $elements['#options'];
}
if (is_array($elements['#value'])) {
$value = in_array($elements['#type'], array(
'checkboxes',
'tableselect',
)) ? array_keys($elements['#value']) : $elements['#value'];
foreach ($value as $v) {
if (!isset($options[$v])) {
form_error($elements, $t('An illegal choice has been detected. Please contact the site administrator.'));
watchdog('form', 'Illegal choice %choice in !name element.', array(
'%choice' => $v,
'!name' => empty($elements['#title']) ? $elements['#parents'][0] : $elements['#title'],
), WATCHDOG_ERROR);
}
}
}
elseif ($elements['#type'] == 'select' && !$elements['#multiple'] && $elements['#required'] && !isset($elements['#default_value']) && $elements['#value'] === $elements['#empty_value']) {
$elements['#value'] = NULL;
form_set_value($elements, NULL, $form_state);
}
elseif (!isset($options[$elements['#value']])) {
form_error($elements, $t('An illegal choice has been detected. Please contact the site administrator.'));
watchdog('form', 'Illegal choice %choice in %name element.', array(
'%choice' => $elements['#value'],
'%name' => empty($elements['#title']) ? $elements['#parents'][0] : $elements['#title'],
), WATCHDOG_ERROR);
}
}
}
// While this element is being validated, it may be desired that some calls
// to form_set_error() be suppressed and not result in a form error, so
// that a button that implements low-risk functionality (such as "Previous"
// or "Add more") that doesn't require all user input to be valid can still
// have its submit handlers triggered. The triggering element's
// #limit_validation_errors property contains the information for which
// errors are needed, and all other errors are to be suppressed. The
// #limit_validation_errors property is ignored if submit handlers will run,
// but the element doesn't have a #submit property, because it's too large a
// security risk to have any invalid user input when executing form-level
// submit handlers.
if (isset($form_state['triggering_element']['#limit_validation_errors']) && $form_state['triggering_element']['#limit_validation_errors'] !== FALSE && !($form_state['submitted'] && !isset($form_state['triggering_element']['#submit']))) {
form_set_error(NULL, '', $form_state['triggering_element']['#limit_validation_errors']);
}
elseif (isset($form_state['triggering_element']) && !isset($form_state['triggering_element']['#limit_validation_errors']) && !$form_state['submitted']) {
form_set_error(NULL, '', array());
}
else {
drupal_static_reset('form_set_error:limit_validation_errors');
}
// Make sure a value is passed when the field is required.
if (isset($elements['#needs_validation']) && $elements['#required']) {
// A simple call to empty() will not cut it here as some fields, like
// checkboxes, can return a valid value of '0'. Instead, check the
// length if it's a string, and the item count if it's an array.
// An unchecked checkbox has a #value of integer 0, different than string
// '0', which could be a valid value.
$is_countable = is_array($elements['#value']) || $elements['#value'] instanceof Countable;
$is_empty_multiple = $is_countable && count($elements['#value']) == 0;
$is_empty_string = is_string($elements['#value']) && drupal_strlen(trim($elements['#value'])) == 0;
$is_empty_value = $elements['#value'] === 0;
$is_empty_null = is_null($elements['#value']);
if ($is_empty_multiple || $is_empty_string || $is_empty_value || $is_empty_null) {
// Although discouraged, a #title is not mandatory for form elements. In
// case there is no #title, we cannot set a form error message.
// Instead of setting no #title, form constructors are encouraged to set
// #title_display to 'invisible' to improve accessibility.
if (isset($elements['#title'])) {
form_error($elements, $t('!name field is required.', array(
'!name' => $elements['#title'],
)));
}
else {
form_error($elements);
}
}
}
// Call user-defined form level validators.
if (isset($form_id)) {
form_execute_handlers('validate', $elements, $form_state);
}
elseif (isset($elements['#element_validate'])) {
foreach ($elements['#element_validate'] as $function) {
$function($elements, $form_state, $form_state['complete form']);
}
}
$elements['#validated'] = TRUE;
}
// Done validating this element, so turn off error suppression.
// _form_validate() turns it on again when starting on the next element, if
// it's still appropriate to do so.
drupal_static_reset('form_set_error:limit_validation_errors');
}