Lost Values from parse

jerrygarciuh has asked for the wisdom of the Perl Monks concerning the following question:

I am using a form parsing routine I picked up here at PM without success. I believe I must have misunderstood what it is doing I thought it was doing the equivalent of my $variable = $q->param( 'variable' ); for each param it receives but when I try to print values 2 things happen:
1)The script dies if the variable wasn't declared with my. I thought the foreach my $str (@names) was taking care of the declarations.
2) The params are undef when I try to print them (even inside the parse_form sub. However, if I add lines like

    my $date = $q->param( 'date' );
    my $filet = $q->param( 'filet');
[download]

I get my params and their values. Will someone please point out whatever it is that I fail to comprehend about this process.
TIA
jg

#!/usr/local/bin/perl -wT
use strict;

use lib qw(/home/nolaflash/www/local_mods);

use CGI ':standard';
use CGI::Carp qw/fatalsToBrowser /;
use CGI::Pretty qw( :html3 );


my $q = CGI->new();

if ( $q->param() ) {
    parse_form();
}

sub parse_form {
    my $sr;
    my @names=$q->param;
    foreach my $str (@names) {
        $sr->{$str} =$q->param($str);
    }

    print $q->header,start_html," @names $action $time $date filet = $
+filet",end_html;
    exit;
}
[download]

_____________________________________________________
It's not my tree.

Comment on Lost Values from parse_form Sub Select or Download Code

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(jeffa) Re: Lost Values from parse_form Sub by jeffa (Bishop) on Mar 10, 2002 at 15:39 UTC
`print $q->header,start_html," @names $action $time $date filet = $file +t",end_html;` [download] You have 4 undeclared variables, don't you mean to use those as hash keys instead? `print $q->header,start_html, $sr->{action}, $sr->{time}; # etc.` [download] But, why are you even copying from $q->param? UPDATE: Sometimes i use grep to grab out things like submit buttons, say that i have a form with multiple submits whose names are prefaced with 'go_': `my @choice = grep /go_/, $q->param;` [download] No need to copy the contents of CGI::param() to an array, loop through it copying each value to hash ... grep! UPDATE UPDATE: and if you are saying "hey, that only gets the names, what about the values?" `my %choice = map {$_ => $q->param($_)} grep /go_/, $q->param();` [download] jeffa L-LL-L--L-LL-L--L-LL-L-- -R--R-RR-R--R-RR-R--R-RR B--B--B--B--B--B--B--B-- H---H---H---H---H---H--- (the triplet paradiddle with high-hat)	[reply] [d/l] [select]
Re: (jeffa) Re: Lost Values from parse_form Sub by jerrygarciuh (Curate) on Mar 10, 2002 at 17:43 UTC
OK I appreciate the simplicity of the importing of the param info into the hash, and I see now that I was receiving the values but not accessing them correctly. This leads me to a couple of questions: Was I making an anonymous hash with my sub? That would explain why the variables were undef, because they were really vars, just hash keys right? So how would I add a line(s) so that the sub would automatically translate param( 'this' ) into $this and assign the value it received? I guess I should use map on the hash keys and values somehow? I realize the 'right' way is probably just to use the hash as it is, but I really like having `$foo = "bar"` to work with. Any help greatly appreciated. TIA jg _____________________________________________________ It's not my tree.	[reply] [d/l] [select]
(jeffa) 3Re: Lost Values from parse_form Sub by jeffa (Bishop) on Mar 10, 2002 at 18:03 UTC
First question: no, the hash was not anonymous, you named it $sr - it is, however, a hash reference. Second question: don't do that!! The right way is indeed to use a hash, but here is the wrong way just for you: (and notice no use strict) `use CGI; # don't use ':standard' unless you don't want OO CGI.pm my $q = CGI->new(); $$_ = $q->param($_) for $q->param(); print "$foo and $bar\n";` [download] This works when run like so: $ perl foo.cgi "foo=baz&bar=qux" baz and qux But using symbolic references is bad practice. Please, for your sanity down the road, stick with hashes to store 'dynamic' variable names. jeffa L-LL-L--L-LL-L--L-LL-L-- -R--R-RR-R--R-RR-R--R-RR B--B--B--B--B--B--B--B-- H---H---H---H---H---H--- (the triplet paradiddle with high-hat)	[reply] [d/l]