Chèn file javascript css ở mọi trang trong WordPress

function my_enqueue($hook) {
    if( 'edit.php' != $hook )
        return;
    wp_enqueue_script( 'my_custom_script', plugin_dir_url( __FILE__ ) . '/myscript.js' );
}
#enqueuing on admin pages
add_action( 'admin_enqueue_scripts', 'my_enqueue' );

add_action( 'admin_init', 'my_plugin_admin_init' );
function my_plugin_admin_init() {
        /* Register our script. */
        wp_register_script( 'my-plugin-script', plugins_url( '/script.js', __FILE__ ) );
    }

add_action( 'admin_menu', 'my_plugin_admin_menu' );
function my_plugin_admin_menu() {
        /* Add our plugin submenu and administration screen */
        $page_hook_suffix = add_submenu_page( 'edit.php', // The parent page of this submenu
                                  __( 'My Plugin', 'myPlugin' ), // The submenu title
                                  __( 'My Plugin', 'myPlugin' ), // The screen title
				  'manage_options', // The capability required for access to this submenu
				  'my_plugin-options', // The slug to use in the URL of the screen
                                  'my_plugin_manage_menu' // The function to call to display the screen
                               );
 
        /*
          * Use the retrieved $page_hook_suffix to hook the function that links our script.
          * This hook invokes the function only on our plugin administration screen,
          * see: http://codex.wordpress.org/Administration_Menus#Page_Hook_Suffix
          */
        add_action('admin_print_scripts-' . $page_hook_suffix, 'my_plugin_admin_scripts');
    }
 
    function my_plugin_admin_scripts() {
        /* Link our already registered script to a page */
        wp_enqueue_script( 'my-plugin-script' );
    }
 
    function my_plugin_manage_menu() {
        /* Display our administration screen */
    }