gangabass

В самом начале после подключения к БД:

$dbh->do(qq{SET NAMES 'utf8'}) or die $dbh->errstr;

sub tf_Update {

    if ( $w->tf->Text() !~ m/^([0-9]{0,8}(?:[\.,][0-9]{0,2})?)$/ ) {

        $w->tf->Text("");
    }
}

Этот код очищает поле полностью. Если нужно удалять только последний введённый символ, то можно отсекать его от текущего значения поля...

Возможно дело в Excel::Reader::XLSX. Мой код работает:

use Excel::Writer::XLSX;
use Spreadsheet::ParseXLSX;
use threads;
use feature qw(say);
use Encode qw(decode);

my $target_workbook = Excel::Writer::XLSX->new("Result.xlsx");

#Обрабатываю два файла "Sample_Сентябрь_2014.xlsx" и "Sample_Октябрь_2014.xlsx")
my @source_files = glob("Sample_*.xlsx");


my $thread = threads->create(
    sub {
        foreach my $source_file (@source_files) {

            my $reader          = Spreadsheet::ParseXLSX->new();
            my $source_workbook = $reader->parse($source_file);

            my ($target_worksheet_name) = $source_file =~ m/Sample_(.+)\.xlsx$/;

            $target_worksheet_name =
              decode( 'windows-1251', $target_worksheet_name );
            my $target_worksheet =
              $target_workbook->add_worksheet($target_worksheet_name);

            my ($worksheet) = $source_workbook->worksheets();

            my ( $row_min, $row_max ) = $worksheet->row_range();
            my ( $col_min, $col_max ) = $worksheet->col_range();

            foreach my $row ( $row_min .. $row_max ) {

                foreach my $col ( $col_min .. $col_max ) {

                    my $cell = $worksheet->get_cell( $row, $col );
                    my $value = $cell->value();
                    $target_worksheet->write( $row, $col, $value );
                }
            }
        }

        $target_workbook->close();
        exit;
    }
);

$thread->join();

Правильнее использовать парсер. Например, XML::LibXML:

use XML::LibXML;
use feature qw(say);

my $filename = "Sample.xml";

my $parser = XML::LibXML->new();
my $doc    = $parser->parse_file($filename);
my $root   = $doc->getDocumentElement;

foreach my $node ( $doc->findnodes('//ip') ) {
    my $value = $node->textContent();

    say $value;
}

По поводу XML::Simple
Создатель XML::Simple сам предлагает использовать XML::LibXML:

STATUS OF THIS MODULE

The use of this module in new code is discouraged. Other modules are available which provide more straightforward and consistent interfaces. In particular, XML::LibXML is highly recommended.

The major problems with this module are the large number of options and the arbitrary ways in which these options interact - often with unexpected results.

Patches with bug fixes and documentation fixes are welcome, but new features are unlikely to be added.