[FIXED] Include external files in functions.php WordPress

Issue

In my WordPress I have a functions.php file containing 1500 lines of code.

Most of this code comes from a program I wrote that connects to an API and sends data from WordPress to it. I am not a WordPress developer, so I do not know if this is possible. Can you make a different file to keep functions.php clean and then include the external file inside the functions.php?

Solution

You can include external files in functions.php by using either

require_once();

or else you can use

include_once();

The difference between these two is that in the event that the file is not found require will give out a fatal error and then stop executing the rest of the file where as include will only issue a warning but will continue the execution of the file.

Answered By - Vihanga Bandara