public void ViewCatalog(ref BookCatalog obj) => obj.ShowListBook();
public int ViewCatalog(ref BookCatalog _books) { _books.ShowListBook(); return(0); }
public void ViewCatalog(ref BookCatalog obj) => obj.ShowListBook();
public int ViewCatalog(ref BookCatalog _books) { _books.ShowListBook(); return(0); }