Prevents nodes and/or comments to be deleted. #drupal #nodes

prevent_node_deletion.php

<?php

//stop deletion of nodes and comments
function MODULE_form_alter (&$form, &$form_state) {
  //stop any node/comment deletions
  if ((isset($form['operation']['#value']) && $form['operation']['#value'] == 'delete') || $form['#id'] == 'node-delete-confirm' || $form['#id'] == 'comment-confirm-delete') {
  //set a message...
  drupal_set_message('your message');
  //stop people from being able to submit the delete form (and in turn stop the delete)
  unset($form['actions']['submit']);
  //set the "cancel" link text to something else
  $form['actions']['cancel']['#title'] = t('Back to previous page');
}

//Stop the deletion of user accounts
if ($form['#id'] == 'user-multiple-cancel-confirm' || $form['#id'] == 'user-cancel-confirm-form') {
    drupal_set_message(t('You are attempting to delete a user account.  Users on this site cannnot be deleted, to disable this users account, please block the account.  Users with blocked accounts will not be able to login.'), 'error');
    unset($form['user_cancel_method']);
    unset($form['user_cancel_confirm']);
    unset($form['user_cancel_notify']);
    unset($form['actions']['submit']);
    $form['actions']['cancel']['#title'] = t('Back to previous page');
}

This snippet has been taken from here: http://drupal.org/node/506222 and authored by sebanthony