public void DisplayBook(Book book, StringBuilder sb)
{
if (book == null)
{
throw new ArgumentNullException("Book cannot be null.");
}
sb.AppendLine(book.Title);
var coverImage = book.GetCoverImage();
sb.AppendLine("Cover Image: " + coverImage.ImagePath);
foreach (var image in book.ReadOnlyImages)
{
sb.AppendLine(image.ImagePath);
}
}