my $xml_dir = "c://temp";

opendir(DIR, $xml_dir);

my @files = grep { /\.xml$/ } readdir(DIR);
closedir(DIR);

foreach my $file (@files) {
	
	open my $fh, "$xml_dir//$file" or die "can't open $file: $!";
	local $/;
	my $contents = <$fh>;
	close $fh;
	
	print "$file is ";
	if($contents !~ /<order>(.*)<\/order>/s){
		print "NOT ";
	}
	print "valid\n";
}