CGI returns no data

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

Has anyone run into a problem where CGI returns no variables? I'm doing user registration for my website, and I have (yet another) odd problem. One form works fine, but the other form returns no data.

If I use this simple script:

#!/usr/bin/perl
print "Content-type: text/html\n\n";
foreach my $scalar (<STDIN>)
{
       print "Data received is: " . $scalar . "\n\n";
}
[download]

I get output like this:

-----------------------------18908589074631857321096704418
Content-Disposition: form-data; name="TestFormField"
 
435435
-----------------------------18908589074631857321096704418
Content-Disposition: form-data; name="Submit"
 
Continue
-----------------------------18908589074631857321096704418--
[download]

However, if I use this script:

#!/usr/bin/perl
use CGI qw (-debug);
use CGI::Carp qw (fatalsToBrowser);
print "Content-type: text/html\n\n";
print "Dump is:\n";
my $CGIValues = new CGI;
$CGIValues->Dump();
[download]

The dump returns no data whatsoever. My web server error logs and access logs report no anomalies. Where could I go look to find the answer to this (or at least some clues)?

Thanks,
Josh

Comment on CGI returns no data Select or Download Code

Replies are listed 'Best First'.
•Re: CGI returns no data by merlyn (Sage) on Dec 20, 2003 at 20:33 UTC
`$CGIValues->Dump();` [download] What are you expecting that to do, when it says this on the manpage: `The Dump() method produces a string consisting of all the query's name/value pairs formatted nicely as a nested list. This is useful for debugging purposes: print $query->Dump` [download] -- Randal L. Schwartz, Perl hacker Be sure to read my standard disclaimer if this is a reply.	[reply] [d/l] [select]
Re: CGI returns no data by b10m (Vicar) on Dec 20, 2003 at 20:31 UTC
See CGI for more, but it looks like you don't want to actually print the output ;) Taken from that same URL: `print $query->Dump` [download] So in your case, try this as your last line: `print $CGIValues->Dump;` [download] -- b10m	[reply] [d/l] [select]
Re: CGI returns no data by jeffa (Bishop) on Dec 21, 2003 at 04:45 UTC
Just a couple more suggestions: If you are going to use CGI.pm, then get into the habit of using the `header()` method to generate the content header. In fact, that method and `param()` are sometimes the only methods i need from CGI.pm: `use CGI qw(param header); print header; if (param('form_submitted') { # process form and print results/errors, maybe reprint form } else { # print form }` [download] Don't use the name $CGIValues for a CGI.pm object. $CGI or $q will do just fine. The reason is that you don't have a handle to the $CGIValues, you have a handle to a CGI.pm object. If you want a handle to the CGI.pm parameter values, do the following: `my $q = CGI->new; my @CGIValues = values %{$q->Vars};` [download] Seems more appriate for a variable named CGIValues ... although technically the values belong to the parameters, not CGI. More useful and meaningful is: `my %param = $q->Vars; #update: typo (was %q->Vars) thanks BUU` [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: CGI returns no data by CountZero (Bishop) on Dec 21, 2003 at 13:31 UTC
If you use CGI just for the headers, parameter parsing, cookie handling and file uploads (i.e. everything except the HTML-routines), you could consider using CGI::Simple instead. It is a drop-in replacement for CGI.pm CountZero "If you have four groups working on a compiler, you'll get a 4-pass compiler." - Conway's Law	[reply]