Manual:Hooks/EditFilter

Details
$editor - Edit form (see includes/EditPage.php)

$text - Contents of the edit box

$section - Section being edited

&$error - Error message to return

Usage
You have two options for filtering edits:


 * 1) Return false to halt editing. You'll need to handle error messages, etc. yourself.
 * 2) Return true and modify $error. This will cause the page to stay in edit mode and will cause the contents of $error to be displayed above the edit box.  Note: $error should be HTML like: