To create an auto-complete field in Drupal, all you need to do to is to use the From API attribute #autocomplete_path and associate with a custom menu callback that provides the AJAX response for the auto-complete field. The custom menu callback can define the query that needs to be made in the database before a result is returned. The below code can b used to create a multi-select auto-complete field.
The best examples of the auto-complete field in core are the author field in node create and edit and taxonomy auto-complete.
function my_module_menu() {
$items['my-module/my-autocomplete'] = array(
'title' =>'My module autocomplete',
'page callback' => 'my_module_autocomplete',
'access callback' => 'my_access',
'access arguments' => array('my module access'),
'type' => MENU_CALLBACK,
);
return $items;
}
function my_module_autocomplete($string = '') {
$array = drupal_explode_tags($string);
// Fetch last value
$last_string = trim(array_pop($array));
$matches = array();
if ($last_string){
$result = Define Query here...
while($obj = db_fetch_object($result)) {
$prefix = count($array) ? implode(', ', $array) .', ' : '';
$matches[$prefix.$obj->;name] = check_plain($obj->name);
}
}
drupal_json($matches);
}
Reference:
1. Helper function taxonomy_autocomplete in taxonomy module
2. Function user_autocomplete in user module.
