in reply to validation of posted data.

It's already been said here, but it's worth saying again:

Don't try to exclude all `illegal' or `invalid' characters. You'll never get them all. Instead, decide what you will accept, and make sure your input contains that, and nothing else.

I'd write your regexp something like this: 

unless ( $display =~ /^[a-z0-9\-\.]+$/ )
{
    # Invalid input
}

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Re: Re: validation of posted data.
by Cine (Friar) on Jul 31, 2002 at 22:15 UTC
    I've found 
    if ($display =~ /[^\-a-z0-9\.]/) {
  #err
}

    [download]
    to be easiere to read most of the time.
    Also if you _read_ the code, Yours says: unless $display is all good chars make an error. Where this says: If there are any illegal chars make an error. I find the latter easiere to understand.

    T I M T O W T D I
[reply]
[d/l]

      Kind of a tangent, here, but isn't "." acceptable by itself (i.e., unescaped) in a character class, since its function as a metacharacter there wouldn't make much sense?

      BCE
      --Your punctuation skills are insufficient!

[reply]
        Yes I believe it is, but I find it easiere to see that a literal period is required when it is escaped instead of examining the context and determening it from there.

        T I M T O W T D I
[reply]

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