Get only enqueued styles and scripts of the current theme

I am trying to get ONLY the loaded styles and scripts of the current active theme.
I am using preg_match to single out just the theme’s script filenames. If matches are found, then just echo the handles of those filenames so I can dequeue/deregister them.

But the preg_match is not working. I am trying to partial match the current theme url ($currthemeurl) with the filename url ($filenames) of the script. Please notice my commented comments.

function remove_theme_scripts() {

    global $wp_scripts;

    $currthemeurl = get_stylesheet_directory_uri(); 
    //Shows http://mydomain/wp-content/themes/mytheme

    foreach( $wp_scripts->queue as $handle ){

             $obj = $wp_scripts->registered [$handle];
             $handles = $obj->handle;  //something.js
             $filenames = $obj->src; //SHOWS http://mydomain/wp-content/themes/mytheme/js/something.js

            if (preg_match($currthemeurl, $filenames)):
             //MATCH FOUND

             echo $handles;
            else:
             echo "NOTHING Match";
            endif;
     }

}

The first argument of preg_match is supposed to be a pattern, not a string, so it’s probably not comparing the way you expect. Use strpos instead:

function wpse_275760_theme_scripts() {
    global $wp_scripts;

    $stylesheet_uri = get_stylesheet_directory_uri();

    foreach( $wp_scripts->queue as $handle ) {
        $obj = $wp_scripts->registered[$handle];
        $obj_handle = $obj->handle;
        $obj_uri = $obj->src;

        if ( strpos( $obj_uri, $stylesheet_uri ) === 0 )  {
            echo $obj_handle;
        } else {
            echo 'NOTHING Match';
        }
    }
}

strpos() returns the starting position of the match, if there is one. Comparing with === to 0 ensures that the script URL and theme URL match from the beginning, which is what you want, since they will both start with http://mydomain/wp-content/themes/mytheme.