you could do something like this if you wanted to restrict a field to a certain set.
The @wrong array will contain all violating enteries (if you want them in your error msg. 
my $test="%%6ffgg";
die("illegal character found".join(',',@wrong)."\n") if @wrong = $test
+ =~(m/([^a-zA-Z0-9])/g);

output
illegal character found%,%

[download]

HTH

In reply to Re: validating form input by chimni
in thread validating form input by jwlarson3rd

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