Create a Taxonomy

Taxonomies are created using the Taxonomy class. This works identically to the PostType class and holds similar methods.

Create a new taxonomy

To create a new taxonomy pass the taxonomy name to the class constructor. Labels and the slug are generated from the taxonomy name.

use PostTypes\Taxonomy;

// Create a new taxonomy
$genres = new Taxonomy( 'genre' );

// Register the taxonomy to WordPress
$genres->register();

Set names

You can define names by passing an array as the first argument. Only name is required.

$names = [
    'name' => 'genre',
    'singular' => 'Genre',
    'plural' => 'Genres',
    'slug' => 'genres'
];

$genres = new Taxonomy( $names );

$genres->register();

The following names are accepted.

Key
Description
Example

name

is the taxonomy name

required, singular, lowercase, underscores

singular

is the singular label for the taxonomy

e.g 'Genre', 'Category'

plural

is the plural label for the taxonomy

e.g 'Genres', 'Categories'

slug

is the taxonomy slug used in the permalinks

plural, lowercase, hyphens

Add options

You can further customise taxonomies by passing an array of options as the second argument in the constructor.

$options = [
    'hierarchical' => false,
];

$genres = new Taxonomy( 'genre', $options );

$genres->register();

Alternatively, you can set options using the options() method.

$genres = new Taxonomy( 'genre' );

$genres->options( [
    'hierarchical' => false,
] );

$genres->register();

The options match the arguments passed to the register_taxonomy() WordPress function. All available options are on the WordPress Codex.

Add labels

You can define the labels for a taxonomy by passing an array as the third argument in the class constructor.

$labels = [
    'add_new_item' => __( 'Add new Genre' ),
];

$genres = new Taxonomy( 'genres', $options, $labels );

$genres->register();

Alternatively, you can use the labels() method to set the labels for the taxonomy.

$genres = new Taxonomy( 'genre' );

$genres->labels( [
	'add_new_item' => __( 'Add new Genre' ),
] );

$genres->register();

All available labels are on the WordPress Codex

Work with existing Taxonomies

You can work with existing taxonomies by passing the taxonomy name to the Taxonoy constructor. Once you have made your changes you need to register them to WordPress using the register() method.

// Create a new Taxonomy object for an existing taxonomy.
$tags = new Taxonomy( 'post_tag' );

// Modify the taxonomy...

// Regsiter changes to WordPress.
$tags->register();

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