{"id":250,"date":"2025-07-27T06:47:55","date_gmt":"2025-07-27T06:47:55","guid":{"rendered":"https:\/\/mitalgoswami.in\/?p=250"},"modified":"2025-08-27T06:33:40","modified_gmt":"2025-08-27T06:33:40","slug":"advanced-functions-in-wordpress","status":"publish","type":"post","link":"https:\/\/mitalgoswami.in\/?p=250","title":{"rendered":"Advanced Functions in WordPress"},"content":{"rendered":"\n

1. add_action()<\/code><\/h3>\n\n\n\n

Adds a function to a WordPress action hook<\/strong> (e.g., run code at a specific point like page load or admin init).<\/p>\n\n\n\n

function my_custom_function() {
  echo '<p>Hello from add_action!<\/p>';
}
add_action('wp_footer', 'my_custom_function'); \/\/ Hook into footer
<\/code><\/pre>\n\n\n\n
\n\n\n\n
 2. add_filter()<\/code><\/h3>\n\n\n\n
Modifies existing data before it\u2019s displayed.<\/p>\n\n\n\n
function modify_title($title) {
  return ' ' . $title;
}
add_filter('the_title', 'modify_title');
<\/code><\/pre>\n\n\n\n
\n\n\n\n
 3. add_shortcode()<\/code><\/h3>\n\n\n\n
Registers a custom shortcode for use in posts\/pages.<\/p>\n\n\n\n
function my_shortcode_function($atts) {
  return \"Welcome to my site!\";
}
add_shortcode('welcome', 'my_shortcode_function');
<\/code><\/pre>\n\n\n\n
Use in editor:<\/p>\n\n\n\n
[welcome]
<\/code><\/pre>\n\n\n\n
\n\n\n\n
 4. do_shortcode()<\/code><\/h3>\n\n\n\n
Executes a shortcode from PHP code.<\/p>\n\n\n\n
echo do_shortcode('[welcome]');
<\/code><\/pre>\n\n\n\n
\n\n\n\n
 5. register_nav_menu()<\/code><\/h3>\n\n\n\n
Registers a single menu location.<\/p>\n\n\n\n
function register_my_menu() {
  register_nav_menu('main-menu', 'Main Navigation');
}
add_action('init', 'register_my_menu');
<\/code><\/pre>\n\n\n\n
To display it:<\/p>\n\n\n\n
phpCopyEdit<?php wp_nav_menu(['theme_location' => 'main-menu']); ?>\n<\/code><\/pre>\n\n\n\n
\n\n\n\n
 Custom Post Types (CPT)<\/h2>\n\n\n\n
 register_post_type()<\/code><\/h3>\n\n\n\n
Registers a new content type.<\/p>\n\n\n\n
function create_books_cpt() {
  register_post_type('book', [
    'labels' => [
      'name' => 'Books',
      'singular_name' => 'Book',
    ],
    'public' => true,
    'has_archive' => true,
    'rewrite' => ['slug' => 'books'],
    'supports' => ['title', 'editor', 'thumbnail'],
    'show_in_rest' => true, \/\/ For Gutenberg
  ]);
}
add_action('init', 'create_books_cpt');
<\/code><\/pre>\n\n\n\n
 Access via: yourdomain.com\/books\/<\/code><\/strong><\/p>\n\n\n\n
\n\n\n\n
 Custom Taxonomy<\/h2>\n\n\n\n
 register_taxonomy()<\/code><\/h3>\n\n\n\n
Registers a custom category or tag-like taxonomy.<\/p>\n\n\n\n
function create_book_genre_taxonomy() {
  register_taxonomy('genre', 'book', [
    'labels' => [
      'name' => 'Genres',
      'singular_name' => 'Genre',
    ],
    'hierarchical' => true,
    'public' => true,
    'rewrite' => ['slug' => 'genre'],
    'show_in_rest' => true,
  ]);
}
add_action('init', 'create_book_genre_taxonomy');
<\/code><\/pre>\n\n\n\n
\n\n\n\n
 Display Custom Post Types & Taxonomy<\/h3>\n\n\n\n
Loop for CPT:<\/h4>\n\n\n\n
$args = ['post_type' => 'book'];
$loop = new WP_Query($args);
while ($loop->have_posts()) : $loop->the_post();
  the_title('<h2>', '<\/h2>');
  the_content();
endwhile;
wp_reset_postdata();
<\/code><\/pre>\n\n\n\n
Display taxonomy:<\/h4>\n\n\n\n
$genres = get_the_term_list(get_the_ID(), 'genre', '', ', ');
echo 'Genres: ' . $genres;
<\/code><\/pre>\n\n\n\n
\n\n\n\n
 Widget Areas (Sidebars)<\/h2>\n\n\n\n
 register_sidebar()<\/code><\/h3>\n\n\n\n
Registers a new widget-ready area.<\/p>\n\n\n\n
function custom_widget_area() {
  register_sidebar([
    'name' => 'Sidebar Widgets',
    'id' => 'sidebar-1',
    'before_widget' => '<section class=\"widget\">',
    'after_widget' => '<\/section>',
    'before_title' => '<h2>',
    'after_title' => '<\/h2>',
  ]);
}
add_action('widgets_init', 'custom_widget_area');
<\/code><\/pre>\n\n\n\n
\n\n\n\n
 dynamic_sidebar()<\/code><\/h3>\n\n\n\n
Displays a registered widget area:<\/p>\n\n\n\n
<?php if (is_active_sidebar('sidebar-1')) : ?>
  <?php dynamic_sidebar('sidebar-1'); ?>
<?php endif; ?>
<\/code><\/pre>\n\n\n\n
\n\n\n\n
\u2705 Summary Cheat Sheet<\/h2>\n\n\n\n
Feature<\/th>Function<\/th><\/tr><\/thead>
Hook into page<\/td>add_action()<\/code>, add_filter()<\/code><\/td><\/tr>
Shortcodes<\/td>add_shortcode()<\/code>, do_shortcode()<\/code><\/td><\/tr>
Custom Menu<\/td>register_nav_menu()<\/code><\/td><\/tr>
CPT<\/td>register_post_type()<\/code><\/td><\/tr>
Custom Taxonomy<\/td>register_taxonomy()<\/code><\/td><\/tr>
Widget Area<\/td>register_sidebar()<\/code> + dynamic_sidebar()<\/code><\/td><\/tr><\/tbody><\/table><\/figure>\n","protected":false},"excerpt":{"rendered":"
1. add_action() Adds a function to a WordPress action hook (e.g., run code at a specific point like page load or admin init). function my_custom_function() { echo ‘<p>Hello from add_action!<\/p>’;}add_action(‘wp_footer’, ‘my_custom_function’); \/\/ Hook into footer 2. add_filter() Modifies existing data before it\u2019s displayed. function modify_title($title) { return ‘ ‘ . $title;}add_filter(‘the_title’, ‘modify_title’); 3. add_shortcode() Registers […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[12,2],"tags":[],"class_list":["post-250","post","type-post","status-publish","format-standard","hentry","category-unit-5","category-wordpress"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/posts\/250","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=250"}],"version-history":[{"count":1,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/posts\/250\/revisions"}],"predecessor-version":[{"id":251,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/posts\/250\/revisions\/251"}],"wp:attachment":[{"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=250"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=250"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=250"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}