Insert my files inside a custom table after upload? How to insert my uploaded files inside a custom table (as managed_file) after upload inside a custom form on DRupal 8 please ?

For moment, I have :

$form['images']['new']['local'] = array(
  '#title' =&gt; t('Upload Images'),
  '#type' =&gt; 'managed_file',


I need to use jquery, element_validate ? Other ?
Thanks.
Don't. It's a fundamentally bad idea to store data in custom table in Drupal 8. There are enough APIs and no support for that. Of course, hooks are still there so you can implement hook_entity_presave and then take the field data and write it out... but just say no :)