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Re: Allow only letters and numbers?

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From:
Jeff 'japhy' Pinyan
Date:
February 21, 2002 16:58
Subject:
Re: Allow only letters and numbers?
Message ID:
Pine.GSO.4.21.0202211953520.19708-100000@crusoe.crusoe.net
On Feb 22, Daniel Falkenberg said:

>The code below of coarse will count all characters in the string $string
>
>$string = "4556jhkl";
>
>$count = $string =~ tr/a-zA-Z0-9//;
>
>How would I go about only allowing numbers and letters of the alpahbet?

You could say:

  if ($string =~ tr/a-zA-Z0-9//c) {
    print "bad character found";
  }

The /c modifier means "invert the set", so that tr/aeiou//c scans for
characters that are NOT a, e, i, o, or u.

If a regex is want you want to use, I'd suggest:

  if ($string =~ /[^a-zA-Z0-9]/) {
    # bad character found
  }

-- 
Jeff "japhy" Pinyan      japhy@pobox.com      http://www.pobox.com/~japhy/
RPI Acacia brother #734   http://www.perlmonks.org/   http://www.cpan.org/
** Look for "Regular Expressions in Perl" published by Manning, in 2002 **
<stu> what does y/// stand for?  <tenderpuss> why, yansliterate of course.
[  I'm looking for programming work.  If you like my work, let me know.  ]


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