public void OnISBNChanged()
{
if (ISBNUtils.IsValid(ISBN))
{
PublisherId = ISBNUtils.GetPublisherId(ISBN);
}
}
private IObjectValidator GetValidator(IList <Book> books = null, IList <Publisher> publishers = null)
{
var builder = new ValidationBuilder <Book>();
builder.RuleFor(book => book.ISBN)
.Must(ISBNUtils.IsValid)
.WithMessage("ISBN is not valid");
builder.RuleFor(book => book.ISBN)
.Must(isbn => publishers == null ||
publishers.Any(publisher => publisher.Id == ISBNUtils.GetPublisherId(isbn)))
.WithMessage("Publisher that owns such ISBN does not exist")
.Must(isbn => books == null ||
!books.Any(book => !ReferenceEquals(book, this) && book.ISBN == isbn))
.WithMessage("ISBN should be unique")
.AllWhen(book => ISBNUtils.IsValid(book.ISBN));
builder.RuleFor(book => book.Name)
.NotEmpty()
.WithMessage("Name can't be empty");
builder.RuleFor(book => book.AgeRestriction)
.NotEmpty()
.WithMessage("Age Restriction can't be empty")
.Matches(@"^\d+\+$")
.WithMessage("Age Restriction has wrong format");
return(builder.Build(this));
}