Vocabulary or Taxonomy load in Drupal 8.

If we have vocabulary/taxonomy name then we can easily load by loadTree, follow the syntax.

$tree = \Drupal::entityTypeManager()->getStorage('taxonomy_term')->loadTree('write vocabulary machine name here');
foreach ($tree as $term) {
  echo $term->tid.' - '.$term->name;
}

Example:
$select_category .= '<select><option value="0">- Select -</option>';
$tree = \Drupal::entityTypeManager()->getStorage('taxonomy_term')->loadTree('product_family'); //here product_family is machine name of Product Family taxonomy.
foreach ($tree as $term) {
$select_category .= '<option value="' . $parent . '_' . $term->tid . '">' . $term->name . '</option>';
}
$select_category .= '</select>';


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