public override string ToString() { if (String.IsNullOrEmpty(ISBN) || String.IsNullOrEmpty(Author) || String.IsNullOrEmpty(Name) || String.IsNullOrEmpty(Publisher)) { return(base.ToString()); } return(ISBN + Author + Name + Publisher + Year + Pagesquantity.ToString() + Price.ToString()); }
public string ToString(string format, IFormatProvider provider) { if (String.IsNullOrEmpty(format)) { format = "G"; } if (provider == null) { provider = CultureInfo.CurrentCulture; } switch (format.ToUpperInvariant()) { case "AN": return($"AuthorName: {Author}, Title: {Name}"); case "ANPY": return($"AuthorName: {Author}, Title: {Name}, Publisher: {Publisher}, Year: {Year.ToString(provider)}"); case "IANPYP": return($"ISBN 13: {ISBN}, AuthorName: {Author}, Title: {Name}, Publisher: {Publisher}, Year: {Year.ToString(provider)}, Price: {Price.ToString(provider)}"); case "ANPP": return($"AuthorName: {Author}, Title: {Name}, Publisher: {Publisher}, Price: {Price.ToString(provider)}"); case "G": return($"ISBN 13: {ISBN}, AuthorName: {Author}, Title: {Name}, Publisher: {Publisher}, Year: {Year.ToString(provider)}, Number of pages: {Pagesquantity.ToString(provider)}, Price: {Price.ToString(provider)}"); default: throw new FormatException(String.Format("The {0} format string is not supported.", format)); } }