What is WordPress Hooks?
WordPress Hooks allows your developer to easily tie their own code in with the WordPress core code base, themes, Plugins. Hooks has the two types “Action and Filter”.
Action allows you to add data or change how WordPress operates. Callback functions for action will return at a specific point in the execution of WordPress and can perform some kind of a task, like echoing output to the user or inserting something into the database
Filters are the ability to change data during the execution of WordPress. Callback functions for Filters will accept a variable, modify it, and return it. It works in an isolated manner, and should never affect global variables and output.
WordPress provides many hooks. But you can create your own so that other developers can extend and modify your plugin or theme.
Purpose of WordPress Hooks:
The primary purpose of hooks is to automatically run a function. In addition, this technique also has the ability to modify, extend, or limit the functionality of a theme or plugin.
WordPress Hooks are a crucial WordPress Features that allows developers to insert custom code into WordPress’s PHP processing, at specified junctions during that processing.
Filters are passed code or makeup by their filter hooks, they modify what they are passed, and must return the result back for WordPress to use its regular processing.
Action, by contrast, do not need to return a value, often are not passed specific parameters by their action hooks.
How to use Action Hooks in WordPress:
Action Hooks are a very effective tool in WordPress and you can be used to perform functions (actions) in specific places of themes or plugins. For example, we are taking ‘Total’ theme, use action hooks to change the output or add the own custom code easily.
We need to know the below action hooks for better understand of how hooks are work.
- do_action() – place of “hooked” functions are run.
- add_action() – attaches a function to a hook.
- remove_action() – removes a function attached to a specified action hook.
Types of Action and Filter Hooks:
- Actions Run During a Typical Request
- Actions Run During an Admin Page Request
- Post, Page, Attachment, and Category Actions (Admin)
- Comment, Ping, and Trackback Actions
- Blogroll Actions
- Feed Actions
- Template Actions
- Administrative Actions
- Dashboard “Right Now” Widget Actions
- Post, Page, and Attachment (Upload) Filters
- Comment, Trackback, and Ping Filters
- Category and Term Filters
- Link Filters
- Date and Time Filters
- Author and User Filters
- Blogroll Filters
- Blog Information and Option Filters
- General Text Filters
- Administrative Filters
- Rich Text Editor Filters
- Template Filters
- Registration & Login Filters
- Redirect/Rewrite Filters
- WP_Query Filters
- Media Filters
- Advanced WordPress Filters
- Admin Bar
How to Add and Remove Your Own Functions
You first need to know a few information about Hooks. For actions, you’ll know the name of the hook and when exactly it runs.
For filters, you need to know the name of the hook and you are going to get and have to return, as well.
How to Hook into an Action
add_action( $hook, $function_to_add, $priority, $accepted_args );
The required parameters of the add_action function are the hook and function to add.
How to Hook into a Filter
add_filter( $tag, $function_to_add, $priority, $accepted_args );
In filter, the function_to_add both receives a value and has to return it at the end of the function.
Why use hooks?
- Change almost anything in WordPress, even a quite fundamental thing because a lot of WordPress’s core functions use actions and filters;
- Make changes easily: you can make some incredible changes very quickly and easily.
- Change a theme’s behavior at the source, rather than trying to retro-fit an inappropriate solution with HTML and CSS;
- Make your own changes easy to understand and easier to debug, because your code is reduced to a minimum;
- Each piece of code is a small unit in your functions.php so, you can Enable and disable your changes easily.
- Make your changes relatively upgrade-proof because you no longer need to edit or copy WordPress or any themes and plugins core files;
- Share your knowledge and swap code snippets with others.
We hope this article illustrates the WordPress Hooks and its features. For more information, follow us on Twitter and Facebook and For video tutorials, subscribe to our YouTube channel ServerCake India.