Drupal 8 add message

 \Drupal::messenger()->addMessage($message, 'status');
 \Drupal::messenger()->addMessage($message, 'warning');
 \Drupal::messenger()->addMessage($message, 'error');

Source: api.drupal.org

Drupal set message

$messenger = \Drupal::messenger();
$messenger->addMessage('STUFF', $messenger::TYPE_WARNING);

Source: api.drupal.org

Similar codes

0 vote481 views1 answer
Drupal sync directory in settings.php
PHP Drupal
0 vote445 views1 answer
Drupal 9 Get taxonomy term objects by vocabulary machine name vid
PHP Drupal
0 vote481 views1 answer
Drupal 8 user_load
PHP Drupal
0 vote488 views1 answer
Drupal 9 custom local stream wrapper
PHP Drupal
0 vote423 views1 answer
Provide filter condition in autocomplet field in drupal form using property
PHP Drupal
0 vote470 views2 answers
Drupal set message
PHP Drupal
0 vote462 views1 answer
Taxonomy_get_parents drupal 8
PHP Drupal
0 vote460 views1 answer
Drupal 8 / 9 entityTypeManager get multiple comments by cid
PHP Drupal
0 vote408 views1 answer
Drupal 9 custom blocks dependency injection
PHP Drupal
0 vote449 views1 answer
Drupal 9 check if UUD is valid
PHP Drupal