Greetings data67,

If it was me, I'd read through the file, splitting each line and pushing a particular element into an array (if you just want each value in the column) or a hash (if you want distinct fields). The below example uses both together. (Don't do this. Just pick one of the two.)

open(INPUT, '< your-input-file.txt') or die "Badness: $!";
my (@instructors_array, %instructors_hash);
while (<INPUT>) {
  my ($id, $name, $class, $instructor) = split(/!/);
  push @instructors_array, $instructor;
  $instructors_hash{$instructor}++;
}
close(INPUT);
my @array_with_every_entry_sorted = sort @instructors_array;
my @array_with_distinct_entries = sort keys %instructors_hash;

[download]

There's probably a way to do this in one line with map, but I'm not merlyn or IO, and I haven't had my first cup of coffee yet.

-gryphon
code('Perl') || die;

In reply to Re: building Drop down menu - from a flat file by gryphon
in thread building Drop down menu - from a flat file by data67

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