hook_form_FORM_ID_alter

  1. drupal
    1. 6 core.php
    2. 8
    3. 7
Versions
6 hook_form_FORM_ID_alter(&$form, &$form_state)
7 – 8 hook_form_FORM_ID_alter(&$form, &$form_state, $form_id)

Provide a form-specific alteration instead of the global hook_form_alter().

Modules can implement hook_form_FORM_ID_alter() to modify a specific form, rather than implementing hook_form_alter() and checking the form ID, or using long switch statements to alter multiple forms.

Parameters

$form Nested array of form elements that comprise the form.

$form_state A keyed array containing the current state of the form. The arguments that drupal_get_form() was originally called with are available in the array $form_state['build_info']['args'].

$form_id String representing the name of the form itself. Typically this is the name of the function that generated the form.

See also

hook_form_alter()

drupal_prepare_form()

Related topics

Code

modules/system/system.api.php, line 1631

<?php
function hook_form_FORM_ID_alter(&$form, &$form_state, $form_id) {
  // Modification for the form with the given form ID goes here. For example, if
  // FORM_ID is "user_register_form" this code would run only on the user
  // registration form.

  // Add a checkbox to registration form about agreeing to terms of use.
  $form['terms_of_use'] = array(
    '#type' => 'checkbox', 
    '#title' => t("I agree with the website's terms and conditions."), 
    '#required' => TRUE,
  );
}
?>