How to use load_textdomain action in WordPress

Ever wondered how to execute some custom code before your translation files are loaded in WordPress? Let’s talk about the load_textdomain action hook! This hook fires right before the MO translation file is loaded, giving you a chance to add your custom functionality just in time.

To use the load_textdomain action, you need to register it using add_action. You can place this code in the functions.php file of your active theme or, even better, in a custom WordPress plugin. Why a custom plugin? Well, it ensures your customizations remain intact even if you update your theme.

Below are some live examples to help you understand how to use this hook effectively.

Log MO File Loading

In this example, we define a function that logs the MO file being loaded. This function takes two parameters, $domain and $mofile, and is hooked to load_textdomain.

/**
 * Example of load_textdomain usage
 * @param string $domain Unique domain for translation.
 * @param string $mofile Path to the .mo file.
 */
function weplugins_log_mo_file_load($domain, $mofile){
    echo 'loading file "' . $mofile . '" on domain "' . $domain . '"';
}
add_action( 'load_textdomain', 'weplugins_log_mo_file_load' );

Custom Function Execution

Here’s how you can execute a custom function when the load_textdomain action fires. This example demonstrates how to implement additional functionality based on the parameters received.

function weplugins_execute_on_load_textdomain_event($domain, $mofile){
    // Add your custom code here
}
add_action( "load_textdomain", "weplugins_execute_on_load_textdomain_event" , 10, 2);

Removing a Hook Callback

Need to remove a previously registered action? You can do that too! Make sure to provide the same callback function name, priority, and number of arguments as when you added it.

remove_action( "load_textdomain", "weplugins_execute_on_load_textdomain_event", 10, 2 );

If you’re having any trouble using this hook or need custom functionality, feel free to Contact Us. We’re here to help!