If you want to include an external PHP file inside your template (or code), then put that code inside another template (called, say, mycode.php). Put that mycode.php file in your theme folder.
Then you can
get_template_part('mycode'). Note that you do not include the '.php' part as the parameter of get_template_part.
Your code in mycode.php will be executed at the point of the get_template_part call. Note that this is a good way to include an external functions call that is only needed by a template.
More experimentation on how to 'include' a file that has functions inside your template. I learned that the
locate_template command is better in all cases.
get_template_part may not happen 'soon' enough for your page.
So I now use
myfunctions.php is located in the active theme folder. The two 'true' parameters ensure that the file is loaded at the proper time. The first 'true' will load the file if found. The second 'true' will use
require_once instead of a
My use of this was in a template. I needed some functions that would add things to the head (with an
apply_filter('wp_head')). The functions are in the
my_functions.php file. So the template contains the
locate_template first, then the filters for the
This is a clever and useful way to get a file of your functions to load with a template, while not requiring the functions to be available globally - just in your template.