How to get a field value of custom block?

Question

I have a custom block type, called "Features block". I added a field as alternative title (field_block_alt_title is that machine name).

I would like to display this alternative title on frontpage programmatically.

Now, I have this code so far that is displaying the title of blocks:

<?php

use Drupal\Component\Utility\Html;
use Drupal\Core\Render\Element;

function neft_preprocess_region(&$variables) {
  if ($variables['region'] == 'flick') {
    $titles = array();
    $ids = array();
    $block_ids = Element::children($variables['elements']);
    foreach ($block_ids as $block_id) {
      $block_title = Drupal\block\Entity\Block::load($block_id)->label();
      $titles[] =  Html::escape($block_title);
      $ids[] = 'block-' . Html::getUniqueId($block_id);
    }
    if (count($titles) && count($ids)) {
      $tabs = '<ul>';
      foreach ($titles as $key => $title) {
        $tabs .= "<li><a href=\"#$ids[$key]\">$title</a></li>";
      }
      $tabs .= '</ul>';
      $variables['tabs'] = $tabs;
    }
  }
}

Answer 1

Fields of custom blocks are in block content. So you have to load the block content first, before you can get the field value:

$block = \Drupal\block\Entity\Block::load($block_id);
$uuid = $block->getPlugin()->getDerivativeId();
$block_content = \Drupal::service('entity.repository')->loadEntityByUuid('block_content', $uuid);
if ($block_content) {
  $field_value = $block_content->field_block_alt_title->value;
}

Answer 2

I was trying to do the same today and this is the only one that worked for me on the latest Drupal version (8.6.12).

use \Drupal\block_content\BlockContentInterface;

function HOOK_preprocess_block(&$variables)
{

    $content = $variables['elements']['content'];
    if (isset($content['#block_content']) && $content['#block_content'] instanceof BlockContentInterface) {
        $blockType = $content['#block_content']->bundle();

        if ($blockType === 'CUSTOM_BLOCK_TYPE') {
            $variables['FIELD_VALUE_ACCESSIBLE_VIA_TEMPLATE'] = $content['#block_content']->get('FIELD_NAME')->value;
        }

    }
}

Then in your template file.

{{ FIELD_VALUE_ACCESSIBLE_VIA_TEMPLATE }}

Answer 3

You can load the field like:

$alt_title = Drupal\block\Entity\Block::load($block_id)->get('field_block_alt_title')->value;

or

$alt_title = Drupal\block\Entity\Block::load($block_id)->field_block_alt_title->value;

Answer 4

This is how I get field values from custom block in Drupal 8

  $block_id = 6;
  $block_content = \Drupal\block_content\Entity\BlockContent::load($block_id);

  $facebook_link = $block_content->get('field_facebook_link')->getString();
  $instagram_link = $block_content->get('field_instagram_link')->getString();
  $twitter_link = $block_content->get('field_twitter_link')->getString();
  $youtube_link = $block_content->get('field_youtube_link')->getString();

Answer 5

You need to expose the fields from Node to Block variables.

function MYTHEME_preprocess_block(&$variables) {
    if(isset($variables['elements']['content']['#view'])){
        $node = $variables['elements']['content']['#view']->result[0]->_entity;

    if($node){
      if ($node instanceof \Drupal\node\Entity\Node) {

        if ($node->hasField('field_name_1')) {
          $variables['field_name_1'] = $node->get('field_name_1')->value;
          }

        if ($node->hasField('field_name_2')) {
          $variables['field_name_2'] = $node->get('field_name_2')->value;
          }
       }
    }
}

}`

To use in your block--views-block--block-custom.html.twig

<div>
     {{field_name_1}}       
</div>

<div>
     {{field_name_2}}       
</div>

Tested on Drupal 8.5.3