How to set file usage on drupal 8?

问题

How to set file usage on drupal 8 ? and how to use below methods in drupal 8?

1. file_usage_add.
2. file_usage_delete.
3. file_usage_list

回答1:

here i have added equivalent syntax for Drupal 7 and Drupal 8

file_usage_add    -> \Drupal::service('file.usage')->add
file_usage_delete -> \Drupal::service('file.usage')->delete
file_usage_list   -> \Drupal::service('file.usage')->listUsage


//Add / Delete file usage
$entity_type = 'node';
$entity_id = 1;//Node ID
$fid = 1; // The file ID
$file = \Drupal\file\Entity\File::load($fid);
$file_usage = \Drupal::service('file.usage');
$file_usage->add($file, 'mymodule', $entity_type, $entity_id);
$list = $file_usage->listUsage($file);
$file_usage->delete($file, 'mymodule', $entity_type, $entity_id)

//Get usage of a file
$file = \Drupal\file\Entity\File::load($fid);
$file_usage = \Drupal::service('file.usage');
$list = $file_usage->listUsage($file);

回答2:

You can use these methods in Drupal 8:

1. File usage add: \Drupal::service('file.usage')->add
2. File usage delete: \Drupal::service('file.usage')->delete
3. File usage list: \Drupal::service('file.usage')->listUsage

来源：https://stackoverflow.com/questions/52455491/how-to-set-file-usage-on-drupal-8