Bits of .NET

🏷️ More Than Categories and Tags

Posts have categories, tags. Products need brands, sizes, colors. Custom taxonomies create any classification system.

📝 Register Custom Taxonomy

// functions.php
function create_product_taxonomies() {
    // Brand taxonomy (hierarchical like categories)
    register_taxonomy('product_brand', 'product', array(
        'labels' => array(
            'name' => 'Brands',
            'singular_name' => 'Brand',
            'search_items' => 'Search Brands',
            'all_items' => 'All Brands',
            'parent_item' => 'Parent Brand',
            'parent_item_colon' => 'Parent Brand:',
            'edit_item' => 'Edit Brand',
            'update_item' => 'Update Brand',
            'add_new_item' => 'Add New Brand',
            'new_item_name' => 'New Brand Name',
            'menu_name' => 'Brands'
        ),
        'hierarchical' => true,
        'show_ui' => true,
        'show_admin_column' => true,
        'query_var' => true,
        'rewrite' => array('slug' => 'brand'),
        'show_in_rest' => true  // Block editor support
    ));
    
    // Size taxonomy (non-hierarchical like tags)
    register_taxonomy('product_size', 'product', array(
        'labels' => array(
            'name' => 'Sizes',
            'singular_name' => 'Size',
            'search_items' => 'Search Sizes',
            'popular_items' => 'Popular Sizes',
            'all_items' => 'All Sizes',
            'edit_item' => 'Edit Size',
            'update_item' => 'Update Size',
            'add_new_item' => 'Add New Size',
            'new_item_name' => 'New Size Name',
            'menu_name' => 'Sizes'
        ),
        'hierarchical' => false,
        'show_ui' => true,
        'show_admin_column' => true,
        'query_var' => true,
        'rewrite' => array('slug' => 'size'),
        'show_in_rest' => true
    ));
}
add_action('init', 'create_product_taxonomies');

🎯 Display Taxonomy in Template

// Get terms for current post
$brands = get_the_terms(get_the_ID(), 'product_brand');
if ($brands && !is_wp_error($brands)) {
    echo '<div class="product-brand">Brand: ';
    foreach ($brands as $brand) {
        echo '<a href="' . get_term_link($brand) . '">' . $brand->name . '</a>';
    }
    echo '</div>';
}

// Query products by brand
$args = array(
    'post_type' => 'product',
    'tax_query' => array(
        array(
            'taxonomy' => 'product_brand',
            'field' => 'slug',
            'terms' => 'nike'
        )
    )
);
$query = new WP_Query($args);

💡 Use Cases

• Products: Brands, Sizes, Colors, Materials
• Recipes: Cuisine, Diet, Difficulty, Cooking Time
• Movies: Genre, Director, Actor, Year
• Real Estate: Property Type, Location, Price Range