How do I require a file in a shortcode?

I have a shortcode that is working and displaying the problem is that it jumps to the top of the page. If I have any text or other shortcodes above it in the page editor they will be displayed below this one on the front end.

add_shortcode('shortcode_exsample', 'shortcode_name');

function shortcode_name(){
return require_once ( plugin_dir_path(__FILE__) . '/shortcode_file.php');;
};

There is about 259 lines of HTML in the shortcode_file.php file that is why I am doing it this way rather that just having it inside the function.

Any idea on why this is happening would be great. Thank you.

Shortcodes are expected to return content, not echo it out. So if your shortcode_file.php file is straight html, it’s considered being echoed.

If that’s the case, you could do something like :

function shortcode_name(){
    ob_start();
    require_once ( plugin_dir_path(__FILE__) . '/shortcode_file.php');
    $content = ob_get_clean();
    return $content;
};