the following regex looks for a non-numeric character (if it fails then they are all digits - and therefore acceptable) in the $invalue string: 
my $invalue = param( 'INVALUE' );
if ( defined $invalue ) {
    if ( $invalue =~ /\D/ ) {
        $result = "$invalue is *not* a Number@"
    } else {
        $result = "$invalue is a number.";
    }
} else {
    $result = "Enter a value to test."
}

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The same could be achieved with $invalue =~ /^\d+$/ but as we all know... 
$less->{'characters'}->{'typed'} == `"time in the pub" | more`; # :-D

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hope this helps

Update: _doh_!! just re-read your post and realised I would have to quickly whip up a regex to allow "-"s and a possible "." so here it is... 

/^(?:-)?\d+(?:\.\d+)?$/

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oh, and for people who like to leave off a leading 0 on decimals > -1 but < 1... 
/^(?:-)?(?:\d+(?:\.\d+)?|\.\d+)$/

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I would be interested in an optimisation of this if anyone can do better.

In reply to Re: Validating Numbers in CGI Script? by larryk
in thread Validating Numbers in CGI Script? by footpad

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