Perl之读取文本文件

#!/usr/bin/perl -w
#use strict;

my $dir="/perl_case";
$dir=$dir."/";
my $filename="test0823.txt";
my $keysword="ccc:";
my $count="10";
my $begincount=index($keysword,":");
my($file);
open(FILEH,$dir.$filename);
 while(my $test=<FILEH>){
   if((index($test,$keysword))>=0){
 my $test1=substr($test,$begincount+1,$count);
    print "$test1"; 
   }
 }
close(FILEH);

----------------------------------------

test0823.txt内容为：

aaa:111

bbb:222

ccc:333

ddd:444