Everyone posted their own views of how and when to use hashes. Problem is that it's really hard to explain in plain words.

I believe it's hard because it either clicks in your head or not. Well at least it's case with me - once I was introduced to hashes I simply got them as granted.

As someone pointed out - you use hashes for storing any data that has names. Such as database tables and forms. Sometimes it's also good to use hash as a parameter for some function/method (often referred as PARAMHASH). In cases when you have more than few parameters.

Anyway if I understood you - I would use following:
- hash for storing the form data > you get it from CGI that way
- hash for storing file names. As keys you have state options, and as matching values you have file names.

So it ends up with something like: 

my $request = CGI->new();

# Is it a hashref or plain hash ?!?
my $values = $request->Vars();

# Or maybe coming from a config file
my %files = { state1 => 'filename1.csv',
              state2 => 'filename2.csv',
              default => 'default_filename.csv',
            }

my $file_name = $files{default};

if(defined $files{$values{state}}) {
   $file_name = $files{$values{state};
}

# Or something shorter like :
# my $file_name = $files{$values{state}} || $files{default}; 

#open....

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In reply to Re: Use Hash? Array? Still confused after all these years. by techcode
in thread Use Hash? Array? Still confused after all these years. by hmbscully

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