If you're calling the same CGI program to handle different stages of a process, then you need to give it some way to distinguish which stage each call needs to process. The easiest way to do this is to have a hidden input (I usually call it 'mode') on the form.

I often find myself writing CGI programs that look a bit like this:

++. But as a piece of advice given to a newbie, even if your code is meant to be a minimal example, there are some obvious errors that may not be just as obvious to him/her, and that make it fail to even compile:

# Work out which mode we're in
my $mode = param('mode');

# If we have a mode, then call that subroutine
if ($mode && %modes{mode}) {
  $modes->{mode}->();
} else {
  # Otherwise call the default handler
  $modes->{default}->();
}

[download]

Of course it must be $mode in both places above instead of mode, and not %modes{...} but $modes{...}. (Well, unless in Perl 6!) Oh, and %mode is a hash, not a hashref, so there's a superfluous dereferencing arrow too. Incidentally I would avoid the whole hassle of a full fledged if... else with a more concise (and not less clear)

$modes{ param('mode') || 'default' }->();

[download]

(But then I'm sure you knew and just wanted to single out the various steps for instructive purposes and the benefit of the OP in this sense...)

In reply to Re^2: Multiple forms in one CGI file? by blazar
in thread Multiple forms in one CGI file? by lakeTrout

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