I like to use a hash that links regular expressions and parameters. Like so: 
use strict;
use CGI;

my $query=CGI->new();
my %laundry= ( 'name' => '(\w+)',
               'number' => '(\d+)',
               'choice' => ([ABC]),
             );
my %laundered_params;

foreach my $param (keys %laundry) {

  die "Parameter $param not present\n" unless my $input=$cgi->param($p
+aram);
  my $regexp=$laundry{$param};
  $input =~ /$regexp/;
  die "Invalid input for $param\n" unless $laundered_params{$param}=$1
+;

}

[download]
The above code is untested and assumes the use of CGI.

CU
Robartes-

In reply to Re: Validating incoming CGI form data by robartes
in thread Validating incoming CGI form data by Anonymous Monk

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