ÄÖÜäöüß

%C3%84%C3%96%C3%9C%C3%A4%C3%B6%C3%BC%C3%9F

%C4%D6%DC%E4%F6%FC%DF

#!/usr/bin/perl

use strict;
use warnings;

use URI::Escape;
use utf8;
no utf8;

sub say { print @_, "\n" }
sub dumphex { my $l = shift; map {sprintf("\\x%x", ord) } split //,$l }

my $DEBUG = 0;

my $uri;

my %testcase = (
        'latin1' => '%C4%D6%DC%E4%F6%FC%DF',
        'utf8' => '%C3%84%C3%96%C3%9C%C3%A4%C3%B6%C3%BC%C3%9F'
);

sub enc_utf8_to_latin1 {
        no utf8;
        
        my $uri = shift;
        
        $uri = uri_unescape($uri);
        
        $DEBUG && say $uri;
        $DEBUG && say dumphex $uri;
        
        utf8::decode($uri);
        
        $DEBUG && say dumphex $uri;
        
        $uri = uri_escape($uri);
        
        $DEBUG && say $uri;

        return $uri;
}


                # ÄÖÜäöüß als UTF-8 URL encoded
$uri = $testcase{'utf8'} );

say $uri, " = ÄÖÜäöüß als UTF-8 URL encoded";
say enc_utf8_to_latin1($uri), ' = UTF-8 -> Latin1 dekodiert';

say;

                # ÄÖÜäöüß ISO-8859-1 URL encoded
$uri = $testcase{'latin1'} );

say $uri, ' = ÄÖÜäöüß ISO-8859-1 URL encoded';
say enc_utf8_to_latin1($uri), ' = Latin1 -> Latin1 dekodiert';