Re^3: Tweak for my Perl Regex that screens for digits only

When text or letters are input the regex generates an error msg,

Disallowing is a form of validation. And your regexp doesn't disallow what you claim it disallows. If there's a digit anywhere in the string, it doesn't generate an error message.

foreach (
   '416-967-1111',
   'I had 2 glasses of orange juice with my breakfast',
   'I had two glasses of orange juice with my breakfast',
) {
   unless (/\s*\(*\)*\.*\d+\-*\s*/) {
      print("error message\n");
   } else {
      print("no error message\n");
   }
}
[download]

outputs

no error message
no error message
error message
[download]

rather than the desired

no error message
error message
error message
[download]

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Re^4: Tweak for my Perl Regex that screens for digits only by hackermike (Novice) on Jan 25, 2006 at 20:34 UTC
Thanks for your reply-- I only meant to say that I'm not trying to validate that the submitted numbers are in fact a phone number. You are correct, the "regex" I hacked up does not do what I thought it did. I did not test sufficient possibilites. Thanks for pointing that out. Clearly I needed even more assistance than I asked for. It's been something of a ,necessary) game deterring the spammers. I don't want to deter the legit posters with too many hurdles, and yet make it too much work for the spammers to be working my forms. The testing I could think of indicates Roy's regex will allow whatever numbers are entered but no text other than the ext. thx Mike	[reply]
Re^5: Tweak for my Perl Regex that screens for digits only by ikegami (Patriarch) on Jan 25, 2006 at 20:49 UTC
Maybe you should consider a statistical approach. You could use an absolute tolerance: `my $good_chars = $FORM{'phone'} =~ tr/-()0-9. //; $good_chars += 3 if $FORM{'phone'} =~ /ext/i; if (length($FORM{'phone'} - $good_chars) > 4) { # Accept <= 4 bad # Bad phone number! ... }` [download] or a relative tolerance: `my $good_chars = $FORM{'phone'}) =~ tr/-()0-9. //; $good_chars += 3 if $FORM{'phone'} =~ /ext/i; if ($good_chars / length($FORM{'phone'} < 0.80) { # Accept <= 20% bad # Bad phone number! ... }` [download] It would probably be more reliable than trying to find out all the valid characters.	[reply] [d/l] [select]