如何查找代码中的hook以使用add_filter自定义版权信息？

Great question! Figuring out how to hook into someone else’s code can feel a bit tricky at first, but let’s break this down clearly.

First: Look for Existing Hooks in the Code #

Most well-written themes or plugins will include hooks specifically for customizing elements like copyright text. Here’s how to spot them:

• Search for apply_filters() calls: This is the key function that lets you filter/replace content. Look through the third-party code (theme or plugin files) for lines related to copyright output. For example, if you find something like:

  $default_credits = '© ' . date('Y') . ' Theme Name';
  echo apply_filters( 'theme_copyright_credits', $default_credits );
  

  The string theme_copyright_credits is exactly the hook name you need to use with add_filter().
• Use keyword searches: If you don’t know where to start, search the codebase for terms like copyright, credits, footer_text, or even the exact default copyright text you see on your site. This will help you locate the specific code block that outputs the text, then check if it’s wrapped in a filter hook.

If No Existing Hook Exists: Create Your Own (When Possible) #

If the third-party code doesn’t have a filter hook for the copyright text, you have a couple options:

• Modify the code safely: If you’re using a theme, use a child theme to override the template file that outputs the copyright. Replace the hardcoded text with a filter hook. For example, change:

  echo '© 2024 Theme Name. All rights reserved.';
  

  To:

  echo apply_filters( 'my_custom_credits_hook', '© 2024 Theme Name. All rights reserved.' );
  

  Now you can use add_filter('my_custom_credits_hook', 'my_custom_credits'); to replace the content just like you already know how.
• Front-end workarounds (if you can’t modify code): If you can’t edit the original code (e.g., it’s a premium plugin you don’t want to break with updates), you can use JavaScript to replace the text on the front end, or CSS to hide the original copyright and add your own via a custom footer widget. These are less ideal than using hooks, but they work in a pinch.

A Quick Note: Hooks Are Not IDs #

To clarify your last question: you don’t use an HTML ID for hooks. Hooks are custom string names defined by developers in apply_filters() or do_action() calls. The hook name is always the first parameter passed to those functions, not an element’s ID from the front-end HTML.

Example in Action #

Suppose you find this line in a theme’s footer.php:

echo apply_filters( 'storefront_footer_credits', sprintf( __( '© %s Storefront', 'storefront' ), date( 'Y' ) ) );

You’d just add this to your child theme’s functions.php:

add_filter('storefront_footer_credits', 'my_custom_credits');
function my_custom_credits() {
  return '© 2024 My Awesome Store. All rights reserved.';
}

And that’s it—your custom credits will replace the default ones.

内容的提问来源于stack exchange，提问作者sswwqqaa