public virtual bool Validate()
{
char checkDigit = '0';
if (isn.Length == 13)
{
checkDigit = CheckDigitRoutines.generateCheck13digit(isn);
}
else if (isn.Length == 10)
{
checkDigit = CheckDigitRoutines.generateCheckIsbn10Issn(isn, 10);
}
else if (isn.Length == 8)
{
checkDigit = CheckDigitRoutines.generateCheckIsbn10Issn(isn, 8);
}
else if (isn.Length == 16)
{
checkDigit = CheckDigitRoutines.generateCheckIsni(isn);
}
else
{
return(false);
}
return(isn.EndsWith(checkDigit));
}
private void checkTypes()
{
if (isValid && identifierType == IdentifierType.ISBN10)
{
isn = $"{"978"}{isn.Substring(0, 9)}{CheckDigitRoutines.generateCheck13digit($"{"978"}{isn}")}";
identifierType = IdentifierType.ISBN;
}
if (isValid && identifierType == IdentifierType.EANISSN)
{
isn = $"{isn.Substring(3, 7)}{CheckDigitRoutines.generateCheckIsbn10Issn(isn.Substring(3, 7), 8)}";
identifierType = IdentifierType.ISSN;
}
}