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hook_validate

  1. drupal
    1. 4.7
    2. 5
    3. 6
    4. 7 node.api.php
Versions
4.7 hook_validate($node)
5 – 6 hook_validate($node, &$form)
7 hook_validate($node, $form, &$form_state)

Verify a node editing form.

This is a hook used by node modules. It is called to allow the module to verify that the node is in a format valid to post to the site. Errors should be set with form_set_error().

Parameters

$node The node to be validated.

$form The node edit form array.

Return value

None.

To validate nodes of all types (not just nodes of the type(s) defined by this module), use hook_nodeapi() instead.

Changes made to the $node object within a hook_validate() function will have no effect. The preferred method to change a node's content is to use hook_nodeapi($op='presave') instead. If it is really necessary to change the node at the validate stage, you can use function form_set_value().

For a detailed usage example, see node_example.module.

Related topics

Hooks
Allow modules to interact with the Drupal core.

Code

developer/hooks/node.php, line 375

<?php
function hook_validate($node, &$form) {
  if (isset($node->end) && isset($node->start)) {
    if ($node->start > $node->end) {
      form_set_error('time', t('An event may not end before it starts.'));
    }
  }
}
?>