use strict;
use warnings;
use Win32::GUI();
use Win32;
use Win32::FileOp qw(SaveAsDialog);

my $startdir = 'C:\Users';
my $filename = Win32::GUI::GetOpenFileName( -title  => 'Select a file', -directory => $startdir,
    -filter => ["Perl scripts (*.pl, *.pm)" => "*.pl;*.pm", "All files" => "*.*", ],);
if ($filename) {
    my $returnvalue = Win32::MsgBox("Use $filename ?",4,"Use it?");
    if ($returnvalue == 6){
        Win32::MsgBox("Using $filename as input.");
    }
    else{
        Win32::MsgBox("Not using $filename as input.");
    }
    print "--- $filename\n";
}
else {
    print "\$filename was not chosen by Win32::GUI::GetOpenfilename\n";
    exit;
}

my %parameters = (
title => "Output file",
filters => {'Filter 1' => '*.txt;*.log', 'Filter 2' => '*.dat'},
filename => 'output.txt',
);
my $output_file = SaveAsDialog %parameters , "output.txt";
if($output_file){
    Win32::MsgBox("Using $output_file as output.");
}
else{
    Win32::MsgBox("No output file chosen.");
}