form.inc in Drupal 4

File

includes/form.inc

<?php

/**
 * @defgroup form Form generation
 * @{
 * Functions to enable output of HTML forms and form elements.
 *
 * Drupal uses these functions to achieve consistency in its form presentation,
 * while at the same time simplifying code and reducing the amount of HTML that
 * must be explicitly generated by modules. See the reference at
 * http://api.drupal.org/api/HEAD/file/developer/topics/forms_api_reference.html
 * and the quickstart guide at
 * http://api.drupal.org/api/HEAD/file/developer/topics/forms_api.html
 */

/**
 * Check if the key is a property.
 */
function element_property($key) {
  return $key[0] == '#';
}

/**
 * Get properties of a form tree element. Properties begin with '#'.
 */
function element_properties($element) {
  return array_filter(array_keys((array) $element), 'element_property');
}

/**
 * Check if the key is a child.
 */
function element_child($key) {
  return $key[0] != '#';
}

/**
 * Get keys of a form tree element that are not properties (i.e., do not begin with '#').
 */
function element_children($element) {
  return array_filter(array_keys((array) $element), 'element_child');
}

/**
 * Processes a form array and produces the HTML output of a form.
 * If there is input in the $_POST['edit'] variable, this function
 * will attempt to validate it, using drupal_validate_form(),
 * and then submit the form using drupal_submit_form().
 *
 * @param $form_id
 *   A unique string identifying the form. Allows each form to be
 *   themed.  Pass NULL to suppress the form_id parameter (produces
 *   a shorter URL with method=get)
 * @param $form
 *   An associative array containing the structure of the form.
 * @param $callback
 *   An optional callback that will be used in addition to the form_id.
 *
 */
function drupal_get_form($form_id, &$form, $callback = NULL) {
  global $form_values, $form_submitted, $user, $form_button_counter;
  static $saved_globals = array();

  // Save globals in case of indirect recursive call
  array_push($saved_globals, array(
    $form_values,
    $form_submitted,
    $form_button_counter,
  ));
  $form_values = array();
  $form_submitted = FALSE;
  $form_button_counter = array(
    0,
    0,
  );
  $form['#type'] = 'form';

  // Add a token to any form displayed to authenticated users.
  // This ensures that any submitted form was actually requested previously by the user to protect against
  // cross site request forgeries. The default token can be bypassed by setting $form['#token'] to FALSE.
  if (isset($form['#token'])) {
    if ($form['#token'] === FALSE || $user->uid == 0) {
      unset($form['#token']);
    }
    else {
      $form['form_token'] = array(
        '#type' => 'token',
        '#default_value' => drupal_get_token($form['#token']),
      );
    }
  }
  else {
    if ($user->uid) {
      $form['#token'] = $form_id;
      $form['form_token'] = array(
        '#id' => 'edit-' . str_replace('_', '-', $form_id) . '-form-token',
        '#type' => 'token',
        '#default_value' => drupal_get_token($form['#token']),
      );
    }
  }
  if (isset($form_id)) {
    $form['form_id'] = array(
      '#type' => 'hidden',
      '#value' => $form_id,
      '#id' => str_replace('_', '-', "edit-{$form_id}"),
    );
  }
  if (!isset($form['#id'])) {
    $form['#id'] = $form_id;
  }
  $form += _element_info('form');
  if (!isset($form['#validate'])) {
    if (function_exists($form_id . '_validate')) {
      $form['#validate'] = array(
        $form_id . '_validate' => array(),
      );
    }
    elseif (function_exists($callback . '_validate')) {
      $form['#validate'] = array(
        $callback . '_validate' => array(),
      );
    }
  }
  if (!isset($form['#submit'])) {
    if (function_exists($form_id . '_submit')) {

      // we set submit here so that it can be altered but use reference for
      // $form_values because it will change later
      $form['#submit'] = array(
        $form_id . '_submit' => array(),
      );
    }
    elseif (function_exists($callback . '_submit')) {
      $form['#submit'] = array(
        $callback . '_submit' => array(),
      );
    }
  }
  foreach (module_implements('form_alter') as $module) {
    $function = $module . '_form_alter';
    $function($form_id, $form);
  }
  $form = form_builder($form_id, $form);
  if (!empty($_POST['edit']) && ($_POST['edit']['form_id'] == $form_id || $_POST['edit']['form_id'] == $callback)) {
    drupal_validate_form($form_id, $form, $callback);

    // IE does not send a button value when there is only one submit button (and no non-submit buttons)
    // and you submit by pressing enter.
    // In that case we accept a submission without button values.
    if (($form_submitted || !$form_button_counter[0] && $form_button_counter[1]) && !form_get_errors()) {
      $redirect = drupal_submit_form($form_id, $form, $callback);
      if (isset($redirect)) {
        $goto = $redirect;
      }
      if (isset($form['#redirect'])) {
        $goto = $form['#redirect'];
      }
      if ($goto !== FALSE) {
        if (is_array($goto)) {
          call_user_func_array('drupal_goto', $goto);
        }
        elseif (!isset($goto)) {
          drupal_goto($_GET['q']);
        }
        else {
          drupal_goto($goto);
        }
      }
    }
  }

  // Don't override #theme if someone already set it.
  if (!isset($form['#theme'])) {
    if (theme_get_function($form_id)) {
      $form['#theme'] = $form_id;
    }
    elseif (theme_get_function($callback)) {
      $form['#theme'] = $callback;
    }
  }
  if (isset($form['#pre_render'])) {
    foreach ($form['#pre_render'] as $function) {
      if (function_exists($function)) {
        $function($form_id, $form);
      }
    }
  }
  $output = form_render($form);

  // Restore globals
  list($form_values, $form_submitted, $form_button_counter) = array_pop($saved_globals);
  return $output;
}
function drupal_validate_form($form_id, $form, $callback = NULL) {
  global $form_values;
  static $validated_forms = array();
  if (isset($validated_forms[$form_id])) {
    return;
  }

  // Check whether the form token is valid.
  if (isset($form['#token'])) {
    if (!drupal_valid_token($form_values['form_token'], $form['#token'])) {

      // setting this error will cause the form to fail validation
      form_set_error('form_token', t('Validation error, please try again.  If this error persists, please contact the site administrator.'));
    }
  }
  _form_validate($form, $form_id);
  $validated_forms[$form_id] = TRUE;
}
function drupal_submit_form($form_id, $form, $callback = NULL) {
  global $form_values;
  $default_args = array(
    $form_id,
    &$form_values,
  );
  if (isset($form['#submit'])) {
    foreach ($form['#submit'] as $function => $args) {
      if (function_exists($function)) {
        $args = array_merge($default_args, (array) $args);

        // Since we can only redirect to one page, only the last redirect will work
        $redirect = call_user_func_array($function, $args);
        if (isset($redirect)) {
          $goto = $redirect;
        }
      }
    }
  }
  return $goto;
}
function _form_validate($elements, $form_id = NULL) {

  // Recurse through all children.
  foreach (element_children($elements) as $key) {
    if (isset($elements[$key]) && $elements[$key]) {
      _form_validate($elements[$key]);
    }
  }

  /* Validate the current input */
  if (!$elements['#validated']) {
    if (isset($elements['#needs_validation'])) {

      // An empty textfield returns '' so we use empty(). An empty checkbox
      // and a textfield could return '0' and empty('0') returns TRUE so we
      // need a special check for the '0' string.
      if ($elements['#required'] && empty($elements['#value']) && $elements['#value'] !== '0') {
        form_error($elements, t('%name field is required.', array(
          '%name' => $elements['#title'],
        )));
      }

      // Add legal choice check if element has #options. Can be skipped, but then you must validate your own element.
      if (isset($elements['#options']) && isset($elements['#value']) && !isset($elements['#DANGEROUS_SKIP_CHECK'])) {
        if ($elements['#type'] == 'select') {
          $options = form_options_flatten($elements['#options']);
        }
        else {
          $options = $elements['#options'];
        }
        if (is_array($elements['#value'])) {
          $value = $elements['#type'] == 'checkboxes' ? array_keys(array_filter($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', t('Illegal choice %choice in %name element.', array(
                '%choice' => theme('placeholder', check_plain($v)),
                '%name' => theme('placeholder', empty($elements['#title']) ? $elements['#parents'][0] : $elements['#title']),
              )), WATCHDOG_ERROR);
            }
          }
        }
        elseif (!isset($options[$elements['#value']])) {
          form_error($elements, t('An illegal choice has been detected. Please contact the site administrator.'));
          watchdog('form', t('Illegal choice %choice in %name element.', array(
            '%choice' => theme('placeholder', $elements['#value']),
            '%name' => theme('placeholder', empty($elements['#title']) ? $elements['#parents'][0] : $elements['#title']),
          )), WATCHDOG_ERROR);
        }
      }
    }

    // User-applied checks.
    if (isset($elements['#validate'])) {
      foreach ($elements['#validate'] as $function => $args) {
        $args = array_merge(array(
          $elements,
        ), $args);

        // for the full form we hand over a copy of $form_values
        if (isset($form_id)) {
          $args = array_merge(array(
            $form_id,
            $GLOBALS['form_values'],
          ), $args);
        }
        if (function_exists($function)) {
          call_user_func_array($function, $args);
        }
      }
    }
    $elements['#validated'] = TRUE;
  }
}

/**
 * File an error against a form element. If the name of the element is
 * edit[foo][bar] then you may pass either foo or foo][bar as $name
 * foo will set an error for all its children.
 */
function form_set_error($name = NULL, $message = '') {
  static $form = array();
  if (isset($name) && !isset($form[$name])) {
    $form[$name] = $message;
    if ($message) {
      drupal_set_message($message, 'error');
    }
  }
  return $form;
}

/**
 * Return an associative array of all errors.
 */
function form_get_errors() {
  $form = form_set_error();
  if (!empty($form)) {
    return $form;
  }
}

/**
 * Return the error message filed against the form with the specified name.
 */
function form_get_error($element) {
  $form = form_set_error();
  $key = $element['#parents'][0];
  if (isset($form[$key])) {
    return $form[$key];
  }
  $key = implode('][', $element['#parents']);
  if (isset($form[$key])) {
    return $form[$key];
  }
}

/**
 * Flag an element as having an error.
 */
function form_error(&$element, $message = '') {
  $element['#error'] = TRUE;
  form_set_error(implode('][', $element['#parents']), $message);
}

/**
 * Adds some required properties to each form element, which are used
 * internally in the form api. This function also automatically assigns
 * the value property from the $edit array, provided the element doesn't
 * already have an assigned value.
 *
 * @param $form_id
 *   A unique string identifying the form. Allows each form to be themed.
 * @param $form
 *   An associative array containing the structure of the form.
 */
function form_builder($form_id, $form) {
  global $form_values, $form_submitted, $form_button_counter;

  // Initialize as unprocessed.
  $form['#processed'] = FALSE;

  /* Use element defaults */
  if (!empty($form['#type']) && ($info = _element_info($form['#type']))) {

    // overlay $info onto $form, retaining preexisting keys in $form
    $form += $info;
  }
  if (isset($form['#input']) && $form['#input']) {
    if (!isset($form['#name'])) {
      $form['#name'] = 'edit[' . implode('][', $form['#parents']) . ']';
    }
    if (!isset($form['#id'])) {
      $form['#id'] = 'edit-' . implode('-', $form['#parents']);
    }
    $posted = isset($_POST['edit']) && $_POST['edit']['form_id'] == $form_id;
    $edit = $posted ? $_POST['edit'] : array();
    foreach ($form['#parents'] as $parent) {
      $edit = isset($edit[$parent]) ? $edit[$parent] : NULL;
    }
    if (!isset($form['#value']) && !array_key_exists('#value', $form)) {
      if ($posted) {
        switch ($form['#type']) {
          case 'checkbox':
            $form['#value'] = !empty($edit) ? $form['#return_value'] : 0;
            break;
          case 'select':
            if (isset($form['#multiple']) && $form['#multiple']) {
              if (isset($edit) && is_array($edit)) {
                $form['#value'] = drupal_map_assoc($edit);
              }
              else {
                $form['#value'] = array();
              }
            }
            elseif (isset($edit)) {
              $form['#value'] = $edit;
            }
            break;
          case 'textfield':
            if (isset($edit)) {

              // Equate $edit to the form value to ensure it's marked for validation
              $edit = str_replace(array(
                "\r",
                "\n",
              ), '', $edit);
              $form['#value'] = $edit;
            }
            break;
          case 'token':
            $form['#value'] = (string) $edit;
            break;
          default:
            if (isset($edit)) {
              $form['#value'] = $edit;
            }
        }

        // Mark all posted values for validation
        if (isset($form['#value']) && $form['#value'] === $edit || isset($form['#required']) && $form['#required']) {
          $form['#needs_validation'] = TRUE;
        }
      }
      if (!isset($form['#value'])) {
        $function = $form['#type'] . '_value';
        if (function_exists($function)) {
          $function($form);
        }
        else {
          $form['#value'] = $form['#default_value'];
        }
      }
    }
    if (isset($form['#executes_submit_callback'])) {

      // Count submit and non-submit buttons
      $form_button_counter[$form['#executes_submit_callback']]++;

      // See if a submit button was pressed
      if (isset($_POST[$form['#name']]) && $_POST[$form['#name']] == $form['#value']) {
        $form_submitted = $form_submitted || $form['#executes_submit_callback'];
      }
    }
  }

  // Allow for elements to expand to multiple elements, e.g. radios, checkboxes and files.
  if (isset($form['#process']) && !$form['#processed']) {
    foreach ($form['#process'] as $process => $args) {
      if (function_exists($process)) {
        $args = array_merge(array(
          $form,
        ), $args);
        $form = call_user_func_array($process, $args);
      }
    }
    $form['#processed'] = TRUE;
  }

  // Set the $form_values key that gets passed to validate and submit.
  // We call this after #process gets called so that #process has a
  // chance to update #value if desired.
  if (isset($form['#input']) && $form['#input']) {
    form_set_value($form, $form['#value']);
  }

  // Recurse through all child elements.
  $count = 0;
  foreach (element_children($form) as $key) {

    // don't squash an existing tree value
    if (!isset($form[$key]['#tree'])) {
      $form[$key]['#tree'] = $form['#tree'];
    }

    // don't squash existing parents value
    if (!isset($form[$key]['#parents'])) {

      // Check to see if a tree of child elements is present. If so, continue down the tree if required.
      $form[$key]['#parents'] = $form[$key]['#tree'] && $form['#tree'] ? array_merge($form['#parents'], array(
        $key,
      )) : array(
        $key,
      );
    }

    # Assign a decimal placeholder weight to preserve original array order
    if (!isset($form[$key]['#weight'])) {
      $form[$key]['#weight'] = $count / 1000;
    }
    $form[$key] = form_builder($form_id, $form[$key]);
    $count++;
  }
  if (isset($form['#after_build']) && !isset($form['#after_build_done'])) {
    foreach ($form['#after_build'] as $function) {
      if (function_exists($function)) {
        $form = $function($form, $form_values);
      }
    }
    $form['#after_build_done'] = TRUE;
  }
  return $form;
}

/**
 * Use this function to make changes to form values in the form validate
 * phase, so they will be available in the submit phase in $form_values.
 *
 * Specifically, if $form['#parents'] is array('foo', 'bar')
 * and $value is 'baz' then this function will make
 * $form_values['foo']['bar'] to be 'baz'.
 *
 * @param $form
 *   The form item. Keys used: #parents, #value
 * @param $value
 *   The value for the form item.
 */
function form_set_value($form, $value) {
  global $form_values;
  _form_set_value($form_values, $form, $form['#parents'], $value);
}

/**
 * Helper function for form_set_value().
 *
 * We iterate of $parents and create nested arrays for them
 * in $form_values if needed. Then we insert the value in
 * the right array.
 */
function _form_set_value(&$form_values, $form, $parents, $value) {
  $parent = array_shift($parents);
  if (empty($parents)) {
    $form_values[$parent] = $value;
  }
  else {
    if (!isset($form_values[$parent])) {
      $form_values[$parent] = array();
    }
    _form_set_value($form_values[$parent], $form, $parents, $value);
  }
  return $form;
}

/**
 * Renders a HTML form given a form tree. Recursively iterates over each of
 * the form elements, generating HTML code. This function is usually
 * called from within a theme.  To render a form from within a module, use
 * drupal_get_form().
 *
 * @param $elements
 *   The form tree describing the form.
 * @return
 *   The rendered HTML form.
 */
function form_render(&$elements) {
  if (!isset($elements)) {
    return NULL;
  }
  $content = '';
  uasort($elements, "_form_sort");
  if (!isset($elements['#children'])) {
    $children = element_children($elements);

    /* Render all the children that use a theme function */
    if (isset($elements['#theme']) && !$elements['#theme_used']) {
      $elements['#theme_used'] = TRUE;
      $previous = array();
      foreach (array(
        '#value',
        '#type',
        '#prefix',
        '#suffix',
      ) as $key) {
        $previous[$key] = isset($elements[$key]) ? $elements[$key] : NULL;
      }

      // If we rendered a single element, then we will skip the renderer.
      if (empty($children)) {
        $elements['#printed'] = TRUE;
      }
      else {
        $elements['#value'] = '';
      }
      $elements['#type'] = 'markup';
      unset($elements['#prefix'], $elements['#suffix']);
      $content = theme($elements['#theme'], $elements);
      foreach (array(
        '#value',
        '#type',
        '#prefix',
        '#suffix',
      ) as $key) {
        $elements[$key] = isset($previous[$key]) ? $previous[$key] : NULL;
      }
    }

    /* render each of the children using form_render and concatenate them */
    if (!isset($content) || $content === '') {
      foreach ($children as $key) {
        $content .= form_render($elements[$key]);
      }
    }
  }
  if (isset($content) && $content !== '') {
    $elements['#children'] = $content;
  }

  // Until now, we rendered the children, here we render the element itself
  if (!isset($elements['#printed'])) {
    $content = theme($elements['#type'] ? $elements['#type'] : 'markup', $elements);
    $elements['#printed'] = TRUE;
  }
  if (isset($content) && $content !== '') {
    $prefix = isset($elements['#prefix']) ? $elements['#prefix'] : '';
    $suffix = isset($elements['#suffix']) ? $elements['#suffix'] : '';
    return $prefix . $content . $suffix;
  }
}

/**
 * Function used by uasort in form_render() to sort form by weight.
 */
function _form_sort($a, $b) {
  $a_weight = is_array($a) && isset($a['#weight']) ? $a['#weight'] : 0;
  $b_weight = is_array($b) && isset($b['#weight']) ? $b['#weight'] : 0;
  if ($a_weight == $b_weight) {
    return 0;
  }
  return $a_weight < $b_weight ? -1 : 1;
}

/**
 * Retrieve the default properties for the defined element type.
 */
function _element_info($type, $refresh = null) {
  static $cache;
  $basic_defaults = array(
    '#description' => NULL,
    '#attributes' => array(),
    '#required' => FALSE,
    '#tree' => FALSE,
    '#parents' => array(),
  );
  if (!isset($cache) || $refresh) {
    $cache = array();
    foreach (module_implements('elements') as $module) {
      $elements = module_invoke($module, 'elements');
      if (isset($elements) && is_array($elements)) {
        $cache = array_merge_recursive($cache, $elements);
      }
    }
    if (sizeof($cache)) {
      foreach ($cache as $element_type => $info) {
        $cache[$element_type] = array_merge_recursive($basic_defaults, $info);
      }
    }
  }
  return $cache[$type];
}
function form_options_flatten($array, $reset = TRUE) {
  static $return;
  if ($reset) {
    $return = array();
  }
  foreach ($array as $key => $value) {
    if (is_array($value)) {
      form_options_flatten($value, FALSE);
    }
    else {
      $return[$key] = 1;
    }
  }
  return $return;
}

/**
 * Format a dropdown menu or scrolling selection box.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used: title, value, options, description, extra, multiple, required
 * @return
 *   A themed HTML string representing the form element.
 *
 * It is possible to group options together; to do this, change the format of
 * $options to an associative array in which the keys are group labels, and the
 * values are associative arrays in the normal $options format.
 */
function theme_select($element) {
  $select = '';
  $size = $element['#size'] ? ' size="' . $element['#size'] . '"' : '';
  _form_set_class($element, array(
    'form-select',
  ));
  return theme('form_element', $element['#title'], '<select name="' . $element['#name'] . '' . ($element['#multiple'] ? '[]' : '') . '"' . ($element['#multiple'] ? ' multiple="multiple" ' : '') . drupal_attributes($element['#attributes']) . ' id="' . $element['#id'] . '" ' . $size . '>' . form_select_options($element) . '</select>', $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
}
function form_select_options($element, $choices = NULL) {
  if (!isset($choices)) {
    $choices = $element['#options'];
  }

  // array_key_exists() accommodates the rare event where $element['#value'] is NULL.
  // isset() fails in this situation.
  $value_valid = isset($element['#value']) || array_key_exists('#value', $element);
  $value_is_array = is_array($element['#value']);
  $options = '';
  foreach ($choices as $key => $choice) {
    if (is_array($choice)) {
      $options .= '<optgroup label="' . $key . '">';
      $options .= form_select_options($element, $choice);
      $options .= '</optgroup>';
    }
    else {
      $key = (string) $key;
      if ($value_valid && ($element['#value'] == $key || $value_is_array && in_array($key, $element['#value']))) {
        $selected = ' selected="selected"';
      }
      else {
        $selected = '';
      }
      $options .= '<option value="' . check_plain($key) . '"' . $selected . '>' . check_plain($choice) . '</option>';
    }
  }
  return $options;
}

/**
 * Format a group of form items.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used: attributes, title, value, description, children, collapsible, collapsed
 * @return
 *   A themed HTML string representing the form item group.
 */
function theme_fieldset($element) {
  if ($element['#collapsible']) {
    drupal_add_js('misc/collapse.js');
    $element['#attributes']['class'] .= ' collapsible';
    if ($element['#collapsed']) {
      $element['#attributes']['class'] .= ' collapsed';
    }
  }
  return '<fieldset' . drupal_attributes($element['#attributes']) . '>' . ($element['#title'] ? '<legend>' . $element['#title'] . '</legend>' : '') . ($element['#description'] ? '<div class="description">' . $element['#description'] . '</div>' : '') . $element['#children'] . $element['#value'] . "</fieldset>\n";
}

/**
 * Format a radio button.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used: required, return_value, value, attributes, title, description
 * @return
 *   A themed HTML string representing the form item group.
 */
function theme_radio($element) {
  _form_set_class($element, array(
    'form-radio',
  ));
  $output = '<input type="radio" ';
  $output .= 'name="' . $element['#name'] . '" ';
  $output .= 'value="' . $element['#return_value'] . '" ';
  $output .= check_plain($element['#value']) == $element['#return_value'] ? ' checked="checked" ' : ' ';
  $output .= drupal_attributes($element['#attributes']) . ' />';
  if (!is_null($element['#title'])) {
    $output = '<label class="option">' . $output . ' ' . $element['#title'] . '</label>';
  }
  return theme('form_element', NULL, $output, $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
}

/**
 * Format a set of radio buttons.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used: title, value, options, description, required and attributes.
 * @return
 *   A themed HTML string representing the radio button set.
 */
function theme_radios($element) {
  if ($element['#title'] || $element['#description']) {
    return theme('form_element', $element['#title'], $element['#children'], $element['#description'], NULL, $element['#required'], form_get_error($element));
  }
  else {
    return $element['#children'];
  }
}

/**
 * Format a password_confirm item.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used: title, value, id, required, error.
 * @return
 *   A themed HTML string representing the form item.
 */
function theme_password_confirm($element) {
  return theme('form_element', $element['#title'], '<div class="container-inline">' . $element['#children'] . '</div>', $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
}

/*
 * Expand a password_confirm field into two text boxes.
 */
function expand_password_confirm($element) {
  $element['pass1'] = array(
    '#type' => 'password',
    '#size' => 12,
    '#value' => $element['#value']['pass1'],
  );
  $element['pass2'] = array(
    '#type' => 'password',
    '#size' => 12,
    '#value' => $element['#value']['pass2'],
  );
  $element['#validate'] = array(
    'password_confirm_validate' => array(),
  );
  $element['#tree'] = TRUE;
  return $element;
}

/**
 * Validate password_confirm element.
 */
function password_confirm_validate($form) {
  $pass1 = trim($form['pass1']['#value']);
  if (!empty($pass1)) {
    $pass2 = trim($form['pass2']['#value']);
    if ($pass1 != $pass2) {
      form_error($form, t('The specified passwords do not match.'));
    }
  }
  elseif ($form['#required'] && !empty($_POST['edit'])) {
    form_error($form, t('Password field is required.'));
  }

  // Password field must be converted from a two-element array into a single
  // string regardless of validation results.
  form_set_value($form['pass1'], NULL);
  form_set_value($form['pass2'], NULL);
  form_set_value($form, $pass1);
  return $form;
}

/**
 * Format a date selection element.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used: title, value, options, description, required and attributes.
 * @return
 *   A themed HTML string representing the date selection boxes.
 */
function theme_date($element) {
  $output = '<div class="container-inline">' . $element['#children'] . '</div>';
  return theme('form_element', $element['#title'], $output, $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
}

/**
 * Roll out a single date element.
 */
function expand_date($element) {

  // Default to current date
  if (!isset($element['#value'])) {
    $element['#value'] = array(
      'day' => format_date(time(), 'custom', 'j'),
      'month' => format_date(time(), 'custom', 'n'),
      'year' => format_date(time(), 'custom', 'Y'),
    );
  }
  $element['#tree'] = TRUE;

  // Determine the order of day, month, year in the site's chosen date format.
  $format = variable_get('date_format_short', 'm/d/Y');
  $sort = array();
  $sort['day'] = max(strpos($format, 'd'), strpos($format, 'j'));
  $sort['month'] = max(strpos($format, 'm'), strpos($format, 'M'));
  $sort['year'] = strpos($format, 'Y');
  asort($sort);
  $order = array_keys($sort);

  // Output multi-selector for date
  foreach ($order as $type) {
    switch ($type) {
      case 'day':
        $options = drupal_map_assoc(range(1, 31));
        break;
      case 'month':
        $options = drupal_map_assoc(range(1, 12), 'map_month');
        break;
      case 'year':
        $options = drupal_map_assoc(range(1900, 2050));
        break;
    }
    $parents = $element['#parents'];
    $parents[] = $type;
    $element[$type] = array(
      '#type' => 'select',
      '#value' => $element['#value'][$type],
      '#attributes' => $element['#attributes'],
      '#options' => $options,
    );
  }
  return $element;
}

/**
 * Validates the FAPI date type to stop dates like 30/Feb/2006
 */
function date_validate($form) {
  if (!checkdate($form['#value']['month'], $form['#value']['day'], $form['#value']['year'])) {
    form_error($form, t('The specified date is invalid.'));
  }
}

/**
 * Helper function for usage with drupal_map_assoc to display month names.
 */
function map_month($month) {
  return format_date(gmmktime(0, 0, 0, $month, 2, 1970), 'custom', 'M', 0);
}

/**
 * Helper function to load value from default value for checkboxes
 */
function checkboxes_value(&$form) {
  $value = array();
  foreach ((array) $form['#default_value'] as $key) {
    $value[$key] = 1;
  }
  $form['#value'] = $value;
}

/**
 * If no default value is set for weight select boxes, use 0.
 */
function weight_value(&$form) {
  if (isset($form['#default_value'])) {
    $form['#value'] = $form['#default_value'];
  }
  else {
    $form['#value'] = 0;
  }
}

/**
 * Roll out a single radios element to a list of radios,
 * using the options array as index.
 */
function expand_radios($element) {
  if (count($element['#options']) > 0) {
    foreach ($element['#options'] as $key => $choice) {
      if (!isset($element[$key])) {
        $element[$key] = array(
          '#type' => 'radio',
          '#title' => $choice,
          '#return_value' => check_plain($key),
          '#default_value' => $element['#default_value'],
          '#attributes' => $element['#attributes'],
          '#parents' => $element['#parents'],
          '#spawned' => TRUE,
        );
      }
    }
  }
  return $element;
}

/**
 * Format a form item.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used:  title, value, description, required, error
 * @return
 *   A themed HTML string representing the form item.
 */
function theme_item($element) {
  return theme('form_element', $element['#title'], $element['#value'] . $element['#children'], $element['#description'], $element['#id'], $element['#required'], $element['#error']);
}

/**
 * Format a checkbox.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used:  title, value, return_value, description, required
 * @return
 *   A themed HTML string representing the checkbox.
 */
function theme_checkbox($element) {
  _form_set_class($element, array(
    'form-checkbox',
  ));
  $checkbox = '<input ';
  $checkbox .= 'type="checkbox" ';
  $checkbox .= 'name="' . $element['#name'] . '" ';
  $checkbox .= 'id="' . $element['#id'] . '" ';
  $checkbox .= 'value="' . $element['#return_value'] . '" ';
  $checkbox .= $element['#value'] ? ' checked="checked" ' : ' ';
  $checkbox .= drupal_attributes($element['#attributes']) . ' />';
  if (!is_null($element['#title'])) {
    $checkbox = '<label class="option">' . $checkbox . ' ' . $element['#title'] . '</label>';
  }
  return theme('form_element', NULL, $checkbox, $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
}

/**
 * Format a set of checkboxes.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 * @return
 *   A themed HTML string representing the checkbox set.
 */
function theme_checkboxes($element) {
  if ($element['#title'] || $element['#description']) {
    return theme('form_element', $element['#title'], $element['#children'], $element['#description'], NULL, $element['#required'], form_get_error($element));
  }
  else {
    return $element['#children'];
  }
}
function expand_checkboxes($element) {
  $value = is_array($element['#value']) ? $element['#value'] : array();
  $element['#tree'] = TRUE;
  if (count($element['#options']) > 0) {
    if (!isset($element['#default_value']) || $element['#default_value'] == 0) {
      $element['#default_value'] = array();
    }
    foreach ($element['#options'] as $key => $choice) {
      if (!isset($element[$key])) {
        $element[$key] = array(
          '#type' => 'checkbox',
          '#processed' => TRUE,
          '#title' => $choice,
          '#return_value' => $key,
          '#default_value' => isset($value[$key]),
          '#attributes' => $element['#attributes'],
        );
      }
    }
  }
  return $element;
}
function theme_submit($element) {
  return theme('button', $element);
}
function theme_button($element) {

  //Make sure not to overwrite classes
  if (isset($element['#attributes']['class'])) {
    $element['#attributes']['class'] = 'form-' . $element['#button_type'] . ' ' . $element['#attributes']['class'];
  }
  else {
    $element['#attributes']['class'] = 'form-' . $element['#button_type'];
  }
  return '<input type="submit" ' . (empty($element['#name']) ? '' : 'name="' . $element['#name'] . '" ') . 'value="' . check_plain($element['#value']) . '" ' . drupal_attributes($element['#attributes']) . " />\n";
}

/**
 * Format a hidden form field.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used:  value, edit
 * @return
 *   A themed HTML string representing the hidden form field.
 */
function theme_hidden($element) {
  return '<input type="hidden" name="' . $element['#name'] . '" id="' . $element['#id'] . '" value="' . check_plain($element['#value']) . "\" " . drupal_attributes($element['#attributes']) . " />\n";
}
function theme_token($element) {
  return theme('hidden', $element);
}

/**
 * Format a textfield.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used:  title, value, description, size, maxlength, required, attributes autocomplete_path
 * @return
 *   A themed HTML string representing the textfield.
 */
function theme_textfield($element) {
  $size = $element['#size'] ? ' size="' . $element['#size'] . '"' : '';
  $class = array(
    'form-text',
  );
  $extra = '';
  if ($element['#autocomplete_path']) {
    drupal_add_js('misc/autocomplete.js');
    $class[] = 'form-autocomplete';
    $extra = '<input class="autocomplete" type="hidden" id="' . $element['#id'] . '-autocomplete" value="' . check_url(url($element['#autocomplete_path'], NULL, NULL, TRUE)) . '" disabled="disabled" />';
  }
  _form_set_class($element, $class);
  $output = '<input type="text" maxlength="' . $element['#maxlength'] . '" name="' . $element['#name'] . '" id="' . $element['#id'] . '" ' . $size . ' value="' . check_plain($element['#value']) . '"' . drupal_attributes($element['#attributes']) . ' />';
  return theme('form_element', $element['#title'], $output, $element['#description'], $element['#id'], $element['#required'], form_get_error($element)) . $extra;
}

/**
 * Format a form.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used: action, method, attributes, children
 * @return
 *   A themed HTML string representing the form.
 */
function theme_form($element) {

  // Anonymous div to satisfy XHTML compliance.
  $action = $element['#action'] ? 'action="' . check_url($element['#action']) . '" ' : '';
  return '<form ' . $action . ' method="' . $element['#method'] . '" ' . 'id="' . $element['#id'] . '"' . drupal_attributes($element['#attributes']) . ">\n<div>" . $element['#children'] . "\n</div></form>\n";
}

/**
 * Format a textarea.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used: title, value, description, rows, cols, required, attributes
 * @return
 *   A themed HTML string representing the textarea.
 */
function theme_textarea($element) {
  $class = array(
    'form-textarea',
  );
  if ($element['#resizable'] !== false) {
    drupal_add_js('misc/textarea.js');
    $class[] = 'resizable';
  }
  $cols = $element['#cols'] ? ' cols="' . $element['#cols'] . '"' : '';
  _form_set_class($element, $class);
  return theme('form_element', $element['#title'], '<textarea' . $cols . ' rows="' . $element['#rows'] . '" name="' . $element['#name'] . '" id="' . $element['#id'] . '" ' . drupal_attributes($element['#attributes']) . '>' . check_plain($element['#value']) . '</textarea>', $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
}

/**
 * Format HTML markup for use in forms.
 *
 * This is used in more advanced forms, such as theme selection and filter format.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used: prefix, value, children and suffix.
 * @return
 *   A themed HTML string representing the HTML markup.
 */
function theme_markup($element) {
  return $element['#value'] . $element['#children'];
}

/**
* Format a password field.
*
* @param $element
*   An associative array containing the properties of the element.
*   Properties used:  title, value, description, size, maxlength, required, attributes
* @return
*   A themed HTML string representing the form.
*/
function theme_password($element) {
  $size = $element['#size'] ? ' size="' . $element['#size'] . '" ' : '';
  $maxlength = $element['#maxlength'] ? ' maxlength="' . $element['#maxlength'] . '" ' : '';
  _form_set_class($element, array(
    'form-text',
  ));
  $output = '<input type="password" name="' . $element['#name'] . '" id="' . $element['#id'] . '" ' . $maxlength . $size . drupal_attributes($element['#attributes']) . ' />';
  return theme('form_element', $element['#title'], $output, $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
}

/**
 * Format a weight selection menu.
 *
 * @param $element
 *   An associative array containing the properties of the element.
 *   Properties used:  title, delta, description
 * @return
 *   A themed HTML string representing the form.
 */
function theme_weight($element) {
  for ($n = -1 * $element['#delta']; $n <= $element['#delta']; $n++) {
    $weights[$n] = $n;
  }
  $element['#options'] = $weights;
  $element['#type'] = 'select';
  return form_render($element);
}

/**
 * Format a file upload field.
 *
 * @param $title
 *   The label for the file upload field.
 * @param $name
 *   The internal name used to refer to the field.
 * @param $size
 *   A measure of the visible size of the field (passed directly to HTML).
 * @param $description
 *   Explanatory text to display after the form item.
 * @param $required
 *   Whether the user must upload a file to the field.
 * @return
 *   A themed HTML string representing the field.
 *
 * For assistance with handling the uploaded file correctly, see the API
 * provided by file.inc.
 */
function theme_file($element) {
  _form_set_class($element, array(
    'form-file',
  ));
  return theme('form_element', $element['#title'], '<input type="file" name="' . $element['#name'] . '"' . ($element['#attributes'] ? ' ' . drupal_attributes($element['#attributes']) : '') . ' id="' . form_clean_id($element['#id']) . '" size="' . $element['#size'] . "\" />\n", $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
}

/**
 * Sets a form element's class attribute.
 *
 * Adds 'required' and 'error' classes as needed.
 *
 * @param &$element
 *   The form element
 * @param $name
 *   Array of new class names to be added
 */
function _form_set_class(&$element, $class = array()) {
  if ($element['#required']) {
    $class[] = 'required';
  }
  if (form_get_error($element)) {
    $class[] = 'error';
  }
  if (isset($element['#attributes']['class'])) {
    $class[] = $element['#attributes']['class'];
  }
  $element['#attributes']['class'] = implode(' ', $class);
}

/**
 * Remove invalid characters from an HTML ID attribute string.
 *
 * @param $id
 *   The ID to clean
 * @return
 *   The cleaned ID
 */
function form_clean_id($id = NULL) {
  $id = str_replace('][', '-', $id);
  return $id;
}

/**
 * @} End of "defgroup form".
 */

Functions

Name	Description
checkboxes_value	Helper function to load value from default value for checkboxes
date_validate	Validates the FAPI date type to stop dates like 30/Feb/2006
drupal_get_form	Processes a form array and produces the HTML output of a form. If there is input in the $_POST['edit'] variable, this function will attempt to validate it, using drupal_validate_form(), and then submit the form using drupal_submit_form().
drupal_submit_form
drupal_validate_form
element_child	Check if the key is a child.
element_children	Get keys of a form tree element that are not properties (i.e., do not begin with '#').
element_properties	Get properties of a form tree element. Properties begin with '#'.
element_property	Check if the key is a property.
expand_checkboxes
expand_date	Roll out a single date element.
expand_password_confirm
expand_radios	Roll out a single radios element to a list of radios, using the options array as index.
form_builder	Adds some required properties to each form element, which are used internally in the form api. This function also automatically assigns the value property from the $edit array, provided the element doesn't already have an assigned value.
form_clean_id	Remove invalid characters from an HTML ID attribute string.
form_error	Flag an element as having an error.
form_get_error	Return the error message filed against the form with the specified name.
form_get_errors	Return an associative array of all errors.
form_options_flatten
form_render	Renders a HTML form given a form tree. Recursively iterates over each of the form elements, generating HTML code. This function is usually called from within a theme. To render a form from within a module, use drupal_get_form().
form_select_options
form_set_error	File an error against a form element. If the name of the element is edit[foo][bar] then you may pass either foo or foo][bar as $name foo will set an error for all its children.
form_set_value	Use this function to make changes to form values in the form validate phase, so they will be available in the submit phase in $form_values.
map_month	Helper function for usage with drupal_map_assoc to display month names.
password_confirm_validate	Validate password_confirm element.
theme_button
theme_checkbox	Format a checkbox.
theme_checkboxes	Format a set of checkboxes.
theme_date	Format a date selection element.
theme_fieldset	Format a group of form items.
theme_file	Format a file upload field.
theme_form	Format a form.
theme_hidden	Format a hidden form field.
theme_item	Format a form item.
theme_markup	Format HTML markup for use in forms.
theme_password	Format a password field.
theme_password_confirm	Format a password_confirm item.
theme_radio	Format a radio button.
theme_radios	Format a set of radio buttons.
theme_select	Format a dropdown menu or scrolling selection box.
theme_submit
theme_textarea	Format a textarea.
theme_textfield	Format a textfield.
theme_token
theme_weight	Format a weight selection menu.
weight_value	If no default value is set for weight select boxes, use 0.
_element_info	Retrieve the default properties for the defined element type.
_form_set_class	Sets a form element's class attribute.
_form_set_value	Helper function for form_set_value().
_form_sort	Function used by uasort in form_render() to sort form by weight.
_form_validate