Processing and storing custom user data

As user profiles are created or updated, WordPress offers an easy way to register a callback to save custom user data in the site's database.

Getting ready

You should have already followed the Adding custom fields to the user editor recipe to have a starting point for this recipe. The resulting plugin should still be active on your development site. Alternatively, you can get the resulting code directory (ch8/ch2-private-item-text/*) from the book's GitHub page and rename ch2-private-item-text-v3.php to ch2-private-item-text.php. All other .php files can be deleted to avoid confusion when activating the plugin.

How to do it...

Follow these steps to register an action hook to save custom user data:

1. Navigate to the ch2-private-item-text folder of the WordPress plugins directory of your development installation.
2. Open the ch2-private-item-text.php file in a text editor.
3. Add the following lines of code at the...