private string GenerateValidISBN(string isbn, ISBNGenerator generator)
{
return generator(isbn);
}
private string GenerateNewISBN(ISBNGenerator generator)
{
string nextNumber = "";
if (lastNumber != null)
{
double LastISBN = ParseISBNString(lastNumber);
nextNumber = GenerateValidISBN((LastISBN + 1).ToString(), generator);
}
else
{
nextNumber = "000-000-001";
}
lastNumber = nextNumber;
return nextNumber;
}
