UserMultipleCancelConfirm::submitForm

public UserMultipleCancelConfirm::submitForm(array &$form, FormStateInterface $form_state)

public function submitForm(array &$form, FormStateInterface $form_state) {
  $current_user_id = $this->currentUser()->id();

  // Clear out the accounts from the temp store.
  $this->tempStoreFactory->get('user_user_operations_cancel')->delete($current_user_id);
  if ($form_state->getValue('confirm')) {
    foreach ($form_state->getValue('accounts') as $uid => $value) {
      // Prevent programmatic form submissions from cancelling user 1.
      if ($uid <= 1) {
        continue;
      }
      // Prevent user administrators from deleting themselves without confirmation.
      if ($uid == $current_user_id) {
        $admin_form_mock = array();
        $admin_form_state = $form_state;
        $admin_form_state->unsetValue('user_cancel_confirm');
        // The $user global is not a complete user entity, so load the full
        // entity.
        $account = $this->userStorage->load($uid);
        $admin_form = $this->entityManager->getFormObject('user', 'cancel');
        $admin_form->setEntity($account);
        // Calling this directly required to init form object with $account.
        $admin_form->buildForm($admin_form_mock, $admin_form_state);
        $admin_form->submitForm($admin_form_mock, $admin_form_state);
      }
      else {
        user_cancel($form_state->getValues(), $uid, $form_state->getValue('user_cancel_method'));
      }
    }
  }
  $form_state->setRedirect('entity.user.collection');
}