So exactly what is your problem?

You can split /[- ]/, $isbn;, but where you go from there is a good question.

I know that the last group with the single digit is a checksum in ISBN - you should be able to find information on how it's calculated and use that to validate the rest.

Makeshifts last the longest.

In reply to Re: CGI -Perl problem by Aristotle
in thread Validating ISBN numbers? by gant

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