function my_custom_js() {
echo '<script type="text/javascript" src="myjsfile.js"></script>';
}
// Add hook for admin <head></head>
add_action('admin_head', 'my_custom_js');
// Add hook for front-end <head></head>
add_action('wp_head', 'my_custom_js');
echo '<script type="text/javascript" src="myjsfile.js"></script>';
}
// Add hook for admin <head></head>
add_action('admin_head', 'my_custom_js');
// Add hook for front-end <head></head>
add_action('wp_head', 'my_custom_js');
