Drupal 7: Displaying node creation form in a block with image or file upload

If you need to display a node creation form on a separate page, you can use Drupal’s standard page rendering and form loading mechanism:

/**
 * Implements hook_menu().
 */
function node_form_example_menu() {
  $items['create/article'] = array(
    'title' => t('Create article'),
    'page callback' => 'node_form_example_article',
    'access callback' => TRUE,
    'type' => MENU_NORMAL_ITEM,
    'file path' => drupal_get_path('module', 'node'),
    'file' => 'node.pages.inc',
  );
  return $items;
}

/**
 * Example form callback
 */
function node_form_example_article() {
  global $user;
  $type = 'article';
  $form_id = $type . '_node_form';
  $node = new stdClass();
  $node->uid = $user->uid;
  $node->type = $type;
  node_object_prepare($node);
  $output = drupal_get_form($form_id, $node);
  return render($output);
}

Two key parameters in form definition are file path and file, which specify additional files containing the form definition code.

To display the form in a block, define the block and use the previously created function node_form_example_article():

/**
 * Implements hook_block_info().
 */
function node_form_example_block_info() {
  $blocks['node_form_example_block'] = array(
    'info' => t('Create article block'),
    'status' => TRUE,
    'region' => 'sidebar_first',
    'visibility' => BLOCK_VISIBILITY_NOTLISTED,
  );
  return $blocks;
}

/**
 * Implements hook_block_view().
 */
function node_form_example_block_view($delta = '') {
  switch ($delta) {
    case 'node_form_example_block':
      module_load_include('inc', 'node', 'node.pages');
      $block['subject'] = t('Create article block');
      $block['content'] = node_form_example_article();
      break;
  }
  return $block;
}

The form displays correctly and even works, but if it includes image or file upload fields, you’ll likely encounter an error upon upload. To fix this, use the following hook_menu_alter implementation:

/**
 * Implements hook_menu_alter().
 */
function node_form_example_menu_alter(&$items) {
  $items['file/ajax']['file'] = 'node.pages.inc';
  $items['file/ajax']['file path'] = drupal_get_path('module', 'node');
}