perl的文件操作(2)

对于如上面一章所写的下载的文件

01 #!/usr/bin/perl -w

02  

03 use Tk;

04  

05 $Tk::strictMotif = 1;

06  

07 $main = MainWindow->new();

08  

09 $button1 = $main->Button(-text => "Exit",

10                          -command => \&exit_button,

11                          -foreground => "orangered" );

12  

13 $button1->pack();

14 $button1->configure(-background => "white" );

15 $button2 = $main->Button(-text => "Push Me",

16                          -command => \&change_color,

17                          -foreground => "black", 

18                          -background => "steelblue");

19  

20 $button2->pack();

21  

22 MainLoop();

23  

24 sub exit_button {

25     print "You pushed the button!\n";

26     exit;

27 }

28  

29 sub change_color {

30     $button1->configure(-background => "red",

31                         -foreground => "white");

32     $button2->configure(-background => "maroon",

33                         -foreground => "white",

34                         -font       => "-*-times-bold-r-normal-20-140-*");

35 }

如果要去掉前导数字和空格，并且sub前保留一个空行，可用

use strict;
#use warnings;

my $tmp;
my $file="./s2";
my $buffer="./tmp.txt";
open F,"$file" or die $!;
open T,">>$buffer" or die $!;
$^I=".bak"; #空时，则不备份

while (readline F) {
  if (defined) {
    chomp;
    s/.{3}//;
    if (/(\S+)/) {
       if (/\b(sub)/) {
         $tmp=$tmp . "\r\n$_\n"
       }
       else {
         $tmp=$tmp . "$_\n";
       }
    }
  }
}
print $tmp;
print T $tmp;
close T;
close F;
rename ("$buffer","$file") or die ("file in use!");

也可用Tie::File,将文件与数组绑定，这样对数组的修改即对应到对文件的修改

#!/usr/bin/perl -w
use Tie::File;
my $file=shift;
my @array;
tie @array,'Tie::File',$file or die "$!\n";

foreach (@array) {
    chomp;
    s/.{3}//;
    if (/(\S+)/) {
        if (/\b(sub)/) {
                $_="\r\n" . $_ . "\n"
        }
        else {
             $_=$_ . "\n";
       }
    }
}

用此方法唯一的问题是空行无法删除，望有兴趣的读者可以自己研究完善这个代码！

（

附：完成此功能的sed文件

$ cat w_file.sed

#!/bin/sed -f
s/^.\{3\}//g
/^[[:space:]]*$/d
/^sub/ i

运行:

$ ./w_file.sed s2

简洁明了！！

）