Call a function in function.php Wordpress - php

Question

I'm studying PHP and have a basic question,
I have this code in the page portfolio.php
<?php
$args = array(
'post_type' => 'portfolio',
'orderby' => 'menu_order',
'order' => 'ASC',
'posts_per_page' => -1
);
$portfolio_query = new WP_Query($args);
if( $portfolio_query->have_posts() ) :
echo '<div id="primary" class="hfeed">';
while( $portfolio_query->have_posts() ) : $portfolio_query->the_post();
// project url
$portfolio_url = get_post_meta($post->ID, '_zilla_portfolio_project_url', true);
if( !empty($portfolio_url) )
$portfolio_button_copy = get_post_meta($post->ID, '_zilla_portfolio_project_url_copy', true);
?>
I would like to echo $portfolio_url in my function.php
Any reference for more study in this case would be appreciated.

Answer 1

It's not clear what you're trying to do, but if you need to pass a url to a function then you can do so with an argument:
function your_function($url) {
// Do whatever you want with $url here, like:
echo 'A link';
}
You can save the above into functions.php.
Based on your comments, I think what you're trying to do is take your code in portfolio.php and turn it into a function that you can call elsewhere. In that case you need to actually define it as a function:
function get_portfolio_url() {
// Insert your existing code in here...
// Then you can either echo $portfolio_url:
echo $portfolio_url;
// Or you can just return it if you plan on doing other things with it
return $portfolio_url
}
You can insert the above function into functions.php. Then you can call it anywhere with get_portfolio_url(). Technically you would no longer require portfolio.php, since you've created a function that does exactly the same thing. Be aware that you don't need to create separate PHP files for every function you require; you can just define them as separate functions in one location and then call them as necessary (which is essentially what functions.php is for in WordPress; a single file to hold all the functions your theme uses).