function hook_validate

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.

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 $node object within a hook_validate() function will have no effect. The preferred method to change a node's content is to use hook_submit() or hook_nodeapi($op='submit') 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

File

developer/hooks/node.php, line 307

These hooks are defined by node modules, modules that define a new kind of node.

Code

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