How to use get_categories_taxonomy filter in WordPress

get_categories_taxonomy filter

Filters the taxonomy used to retrieve terms when calling get_categories().

To use the get_categories_taxonomy filter, you first have to register it using add_filter. You can write this code into the functions.php of your activated theme or in a custom WordPress Plugin.

At WePlugins, we always prefer to create a custom WordPress Plugin while using hooks so nothing breaks when you update your WordPress theme in the future.

In the below live example, we have defined a function modify_get_categories_taxonomy_defaults which takes 2 parameters and we registered it using add_filter. The first parameter get_categories_taxonomy is the name of the hook, the second parameter modify_get_categories_taxonomy_defaults is the name of the function which needs to be called, the third parameter is the priority of calling the hook if the same hook is used multiple times, and the last parameter is the number of arguments (if any) to be passed in the registered function.

Sometimes, you have to remove a registered hook, so you can use remove_filter to remove the get_categories_taxonomy filter.

Parameters

Below are the 2 parameters required to use this hook.

• $taxonomy : (string) Taxonomy to retrieve terms from.
• $args : (array) An array of arguments. See get_terms().

Live Example 1

Below is an example of how you can use this hook.

  function weplugins_modify_get_categories_taxonomy_defaults($taxonomy, $args) { 
      // Update the $taxonomy variable according to your website requirements and return this variable. You can modify the $taxonomy variable conditionally too if you want.
      return $taxonomy; 
  }
  // add the filter
  add_filter("get_categories_taxonomy", "weplugins_modify_get_categories_taxonomy_defaults", 10, 2);
  

Live Example 2

Here’s how you can remove a hook callback.

  remove_filter("get_categories_taxonomy", "weplugins_modify_get_categories_taxonomy_defaults", 10, 2);
  

Please make sure to provide the same callback function name, priority, and number of arguments while removing the hook callback.

Live Example 3

Another example to modify taxonomy conditionally:

  function weplugins_conditional_modify_get_categories_taxonomy($taxonomy, $args) { 
      if ($taxonomy === 'category') {
          $taxonomy = 'custom_taxonomy';
      }
      return $taxonomy; 
  }
  // add the filter
  add_filter("get_categories_taxonomy", "weplugins_conditional_modify_get_categories_taxonomy", 10, 2);
  

Contact Us

If you need customization or have any trouble using this hook, please Contact Us and we’d be happy to assist you.