Take Action: Adding Functionality to WordPress

Customize WordPress with actions and hooks


1. Actions and Hooks: The Dynamic Duo of WordPress

WordPress, the beloved content management system, is like a Swiss Army knife, versatile and customizable. One of its most powerful tools is the ability to extend its functionality through actions and hooks. Imagine you’re building a house, and you need to add a window. Actions are like the blueprints that tell WordPress where to place the window, while hooks are the nails that hold the window in place. Together, they create a dynamic and flexible framework for customizing your WordPress site.

How to add action on WordPress

© Photographer Anna Nekrashevich

Creating an Action

Syntax and Parameters of the add_action() Function

The add_action() function takes two parameters:

  • $tag: The name of the action to create.
  • $functiontoadd: The name of the function to be executed when the action is triggered.

For example, the following code creates an action named my_action that will be executed when the wp_head action is triggered:

add_action( 'wp_head', 'my_action' );

Examples of Common Actions

WordPress provides a wide range of common actions that you can use to customize your site. Some of the most popular actions include:

  • wp_head: Triggered before the <head> tag is closed.
  • wp_footer: Triggered before the <body> tag is closed.
  • init: Triggered when WordPress is initialized.
  • wp_loaded: Triggered after WordPress has finished loading.
  • wp_enqueue_scripts: Triggered when scripts and styles are enqueued.

Hooking into an Action 🎣

Step 3: Using the do_action() Function 🛠️

To trigger an action, we use the do_action() function. It takes the action name as its argument, and WordPress will execute any functions that are hooked into that action.

do_action( 'my_action' );

This code will execute all the functions that are hooked into the my_action action. It’s like throwing a fishing line into the water and waiting for the fish (functions) to bite!

For example, if we have a function called my_action_callback() that is hooked into the my_action action, it will be executed when we call do_action( 'my_action' ).

function my_action_callback() {
  // Do something...
add_action( 'my_action', 'my_action_callback' );

So, the do_action() function allows us to trigger actions and execute the functions that are hooked into them. It’s a powerful tool for extending WordPress functionality and customizing your site!

Passing Data to Actions

Using the add_filter() Function to Pass Data

Passing data to actions allows you to modify the data before it’s used by the action. This can be useful for things like filtering the content of a post or modifying the output of a function.

To pass data to an action, you can use the add_filter() function. This function takes three parameters:

  1. The name of the action you want to pass data to
  2. The callback function that will modify the data
  3. The priority of the filter (optional)

The callback function should take two parameters:

  1. The data you want to modify
  2. An array of additional arguments (optional)

The following example shows how to use the add_filter() function to pass data to an action:

add_filter('the_content', 'my_filter_function', 10);

function my_filter_function($content) {
  // Modify the content here
  return $content;

In this example, the my_filter_function() function will be called before the the_content action is executed. The function can modify the content of the post and return the modified content.

Creating a Custom Action 📝

WordPress provides a powerful tool called register_action() that allows you to create your own custom actions. This is particularly useful when you want to extend the functionality of your theme or plugin without modifying its core code.

To define a custom action, you simply need to use the following syntax:

register_action( 'my_custom_action', 'my_custom_action_callback' );

Here, my_custom_action is the name of your custom action, and my_custom_action_callback is the function that will be executed when the action is triggered.

Once you’ve defined your custom action, you can use it in your code just like any other built-in action. For example, the following code would trigger the my_custom_action action:

do_action( 'my_custom_action' );

You can also pass data to your custom action by using the add_filter() function. This allows you to modify the data before it is passed to the action callback.

For instance, the following code would pass the $data variable to the my_custom_action action:

add_filter( 'my_custom_action', function( $data ) {
  // Modify the data here
  return $data;
} );

Custom actions are a powerful tool that can be used to extend the functionality of WordPress in a variety of ways. By creating your own custom actions, you can easily add new features to your site without having to modify the core code.

Hooking into a Custom Action 🎣

Once you’ve created your custom action, it’s time to connect it to your code. The do_my_action() function is your hook, allowing you to trigger the action and execute the associated code.


Think of it like a fishing line. The do_my_action() function casts the line, and any code hooked to the custom action will start reeling in the results.

For example, let’s say you have a custom action called “myspecialaction” and a function called “myspecialfunction” that you want to trigger when the action is executed. You can hook the function to the action like this:

add_action( 'my_special_action', 'my_special_function' );

Now, when you call do_my_action(), the my_special_function will be executed, performing the desired task. It’s like having a secret handshake between your code and the custom action, allowing them to communicate and work together seamlessly.

Using Actions to Extend Plugins 🔌

Plugins are like little power-ups for your WordPress site, adding extra features and functionality. But what if you want to tweak a plugin’s behavior to fit your specific needs? That’s where actions come in! 🦸‍♂️

By hooking into a plugin’s actions, you can add your own code to run alongside the plugin’s code. It’s like adding a custom ingredient to a recipe, giving your site a unique flavor. 🌶️

For example, let’s say you have a plugin that adds a contact form to your site. You could hook into the plugin’s action to add a custom field for your visitors to enter their phone number. This way, you can collect more information from your leads without having to code the entire form yourself. It’s like having a superpower to customize your plugins! 🚀

Using Actions to Customize Themes 🎨

WordPress themes are the foundation of your site’s design and functionality. By hooking into theme actions, you can modify the theme’s behavior without touching its core code. It’s like adding a dash of your own flavor to a pre-made cake! 🍰

For example, let’s say you want to add a custom widget area to your sidebar. You can do this by hooking into the widgets_init action. Here’s how:

add_action( 'widgets_init', 'my_custom_widget_area' );

function my_custom_widget_area() {
  register_sidebar( array(
    'name'          => 'My Custom Widget Area',
    'id'            => 'my-custom-widget-area',
    'description'   => 'Add your own widgets here.',
    'before_widget' => '<div class="my-custom-widget">',
    'after_widget'  => '</div>',
    'before_title'  => '<h3 class="my-custom-widget-title">',
    'after_title'   => '</h3>',
  ) );

By hooking into the widgets_init action, you’re extending the theme’s functionality without modifying its code. This makes it easy to customize your theme without breaking it!

Best Practices for Using Actions

Naming Conventions for Actions and Hooks

When creating or using actions and hooks, it’s crucial to follow naming conventions to ensure clarity and avoid conflicts. Use a descriptive name that clearly indicates the purpose of the action or hook. For example, instead of using “myaction,” you could use “displayproduct_details.” This makes it easier for other developers to understand the code and prevents confusion.

Avoiding Conflicts with Other Plugins and Themes

To prevent conflicts with other plugins or themes, prefix your custom action or hook names with a unique identifier. This ensures that they won’t clash with existing actions or hooks. For instance, you could use “myplugindisplayproductdetails” instead of “displayproductdetails.” By following these best practices, you can effectively leverage actions and hooks to enhance the functionality and customization of your WordPress site.


Congratulations, you’ve now got a superpower in your WordPress toolkit! Actions and hooks unlock endless possibilities for customizing and extending your website. They’re like the secret handshake that gives you access to the inner workings of WordPress.

Remember, the key to mastering actions and hooks is practice. Dive into your code, experiment with different scenarios, and see how you can harness their power to make your WordPress site truly unique. Just like a master chef who knows the perfect blend of spices, you’ll become a WordPress wizard who can create a website that’s both functional and fabulous.

So, go forth and conquer the world of WordPress actions and hooks! May your website shine brighter than a thousand suns. ☀️

About David Damstra

Business Leader and Business Developer, Project Manager and Full Stack Developer & Designer Creative Director, Brand Guardian, Minister of Company Culture Co-Author of Professional WordPress. Currently in Third Edition. Seasoned web developer using practical technology to rapidly create standards compliant dynamic websites. Experienced with web development, software development and systems and network management and consulting.