Perl哈希声明错误

Question

I am new to perl and can't seem to find why this snippet is giving me a 500 error.

#!/usr/bin/perl
use strict;
use warnings;
use CGI::Carp qw( fatalsToBrowser );

my ($distance, $weight, $total_gas, $mph, $buffer, $pair, @pairs, $value, $form, $name);
our %FORM = ();

read(STDIN, $buffer, $ENV{'CONTENT_LENGTH'});

@pairs = split(/&/, $buffer);
foreach $pair (@pairs) {
    ($name, $value) = split(/=/, $pair);
    $value =~ tr/+/ /;
    $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
    $FORM{$name} = $value;
}

Everything I tried on the %FORM = (); gives me variable declaration errors.

Answer 1

Are you certain that @pairs contains the values you expect (ie that they are name value pairs split with "="? More than likely $name isn't defined and you can't add an undefined key pair to a hash. Why are you using STDIN to read in values from the query string? Try:

my $q = CGI->new;
my @keys = $q->param;
my %FORM;
foreach my $name (@keys)
{
    my $value = $q->param($name);
    $FORM{$name} = $value;
}

or

my $q = CGI->new;
my %FORM = $q->Vars;

http://perldoc.perl.org/CGI.html

Answer 2

I think you're missing HTTP header. Try adding to put following line before any print:

print "Content-type: text/html\n\n";

Make sure you have enough permissions for script to run. It'll depend on OS you're using.

Also you'd consider using CGI module as mentioned in scrappedcola 's answer. This code will work for both POST and GET:

use strict; use warnings;
use CGI;

my $form = CGI->Vars;
print "Content-type: text/html\n\n";
print "name=".$form->{name};