If you’re willing to create a child theme and put your PHP files in there, this approach is relatively clean. For each file, create a rewrite rule where you specify the path you want to use and the filename that should load. In the example below, /custom-path/ loads custom-file.php from the root of your child theme directory and /custom-path-2/ loads custom-file-2.php. Don’t forget to flush permalinks after adding rewrites.
/*
* Set up a rewrite for each path which should load a file.
*/
function my_standalone_rewrites() {
add_rewrite_rule( '^custom-path/?', 'index.php?standalone=custom-file', 'top' );
add_rewrite_rule( '^custom-path-2/?', 'index.php?standalone=custom-file-2', 'top' );
}
add_action( 'init', 'my_standalone_rewrites' );
/*
* Make `standalone` available as a query var.
*/
function my_query_vars( $vars ) {
$vars[] = 'standalone';
return $vars;
}
add_filter( 'query_vars', 'my_query_vars' );
/*
* If `standalone` is set when parsing the main query, load the standalone file.
*/
function my_standalone_path( &$wp_query ) {
if ( $wp_query->is_main_query() && get_query_var( 'standalone', false ) ) {
// Load filename.php from your child theme root.
get_template_part( get_query_var( 'standalone' ) );
exit;
}
}
add_action( 'parse_query', 'my_standalone_path' );