FAQ 9.16 How do I decode a CGI form?

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9.16: How do I decode a CGI form?

(contributed by brian d foy)

Use the CGI.pm module that comes with Perl. It's quick, it's easy, and
it actually does quite a bit of work to ensure things happen correctly.
It handles GET, POST, and HEAD requests, multipart forms, multivalued
fields, query string and message body combinations, and many other
things you probably don't want to think about.

It doesn't get much easier: the CGI module automatically parses the
input and makes each value available through the "param()" function.

use CGI qw(:standard);

my $total = param( 'price' ) + param( 'shipping' );

my @items = param( 'item' ); # multiple values, same field name

If you want an object-oriented approach, CGI.pm can do that too.

use CGI;

my $cgi = CGI->new();

my $total = $cgi->param( 'price' ) + $cgi->param( 'shipping' );

my @items = $cgi->param( 'item' );

You might also try CGI::Minimal which is a lightweight version of the
same thing. Other CGI::* modules on CPAN might work better for you, too.

Many people try to write their own decoder (or copy one from another
program) and then run into one of the many "gotchas" of the task. It's
much easier and less hassle to use CGI.pm.



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