$h{lc($key)} = $value;

#....

print $h{lc($newkey)};
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updated: fixed typo.

Hash::Case » Hash::Case::Preserve

• Hash::Case
• Hash::Case::Upper
• Hash::Case::Lower

Cheers - L~R

There are the following modules on CPAN that might be helpful:

• Tie::Hash::Approx - Match keys with with approximate strings.
• Tie::Hash::Regex - Match keys using a regex (this may work for case insensitivity)
• Hash::Case - Base class for hashes with casing requirements.
• Hash::Case::Lower - Force all keys to lower case.
• Hash::Case::Upper - Force all keys to upper case.
• Tie::Hash - Base class providing a framework for you to use in deriving your own tied hash.

Personally I would probably start with Tie::Hash, and create your own case-insensitive hash starting with that framework. tie and perltie will contain additional info on the details of tieing hashes.

Update: Fixed a few module names. Thanks Limbic~Region.

You can not do it with a simple hash.

Yes you can. However, that does not mean that you should :-)

my %h = ( 'aDobe' => 'abcd', 'big boss' => 'gcd', 'ADOBe' => 'abcd2' )
+;
my $str = 'AdOBE';
for ( keys %h ) {
   print "$h{$_}\n" if lc $_ eq lc $str;
}
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One way is to standardize on one case for all your keys on insertion, then to force case on retrieval, like this:

%h = (
  lc('adobe')    => 'abcd',
  lc('big boss') => 'gcd',
  );

my $key = 'AdOBe';
$key = lc($key);
print $key;
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As you have probably guessed, perl is case sensitive, so you are paddling upstream from the start.

But it is easy, depending on your circumstance, to force either the keys, or the subsequent comparison, to lower case using lc or upper case using uc.

For example

print $h{lc 'AdOBe'};
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