perl 列出一个目录下的文件的大小

 use strict;
 use warnings;
 use Cwd;
 my $dir = 'd:\\www';
 chdir($dir);
 opendir DIR, $dir or die "Cannot open dir:$!\n";
 my %result;
 while(my $filename = readdir(DIR)){
     next if (($filename eq '.') or ($filename eq '..'));
     if(-d $filename){$result{$filename} = "Is dir";next;}
     my $byts = -s $filename;
     $result{"$filename"} = $byts."byts";
 }
 while((my $key, my $value) = each %result){
     print "$key => $value\n";
 }