---

static void AddBook(string title, float price, int pages, int authorId)
{
    string connectionString = @"Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=Library;Integrated Security=True;";
    string sql = "INSERT INTO Books (Title, Price, Pages, AuthorId) VALUES (@title, @price, @pages, @authorId)";

    using (SqlConnection conn = new SqlConnection(connectionString))
    {
        conn.Open();
        Console.WriteLine("Подключение открыто");

        using (SqlCommand cmd = new SqlCommand(sql, conn))
        {
            cmd.Parameters.AddWithValue("@title", title);
            cmd.Parameters.AddWithValue("@price", price);
            cmd.Parameters.AddWithValue("@pages", pages);
            cmd.Parameters.AddWithValue("@authorId", authorId);

            int rows = cmd.ExecuteNonQuery();
            Console.WriteLine($"Добавлено книг: {rows}");
        }
    }
}