Question

我有一个类似于

的网址

//google.com/Ucomm/Photos/1984 Digital Photos/blah blah/Reflections Magazine/Fall 1984    issue/This is what I want 7-28/TMI_7840_xx.PNG

每个网址都不同但我想要的是相同的部分，它就是文件名之前的部分我想如果我计算了反斜杠的数量，我可以打印出第二个到最后一个和最后一个之间的内容。

所以输出看起来像

This is what I want 7-28

到目前为止我所知道的反斜杠的数量，但我不知道如何打印我需要的东西。

守则：

my $string = $cells[74];
my $count = lc($string) =~ tr/\///;
print $count;

Answer 1

你不需要计算斜杠（那些是正斜杠，而不是反斜杠），只需从最后开始并向后工作。

#!/usr/bin/perl

use strict;
use warnings;
use v5.10;

my $string = "//google.com/Ucomm/Photos/1984 Digital Photos/blah blah/Reflections Magazine/Fall 1984    issue/This is what I want 7-28/TMI_7840_xx.PNG";

say "Version 1";
{
        my @parts = split '/', $string;
        say $parts[-2];
}

say "Version 2"; # if you love regular expressions
{
        my ($captured) = $string =~ m!/([^/]+)/[^/]+$!;
        say $captured;
}

Answer 2

您可以使用basename和dirname：

use File::Basename;

my $str="//google.com/Ucomm/Photos/1984 Digital Photos/blah blah/Reflections Magazine/Fall 1984    issue/This is what I want 7-28/TMI_7840_xx.PNG";

print basename(dirname($str));

或者，split /上的字符串，并采用前一个元素。

Answer 3

您可以使用split

my @data = split('/', $string);
print $data[-2];

Answer 4

将输入分解为数组。问题是：如何识别你想要的领域？按位置？

    #!/usr/bin/env perl

    use strict;
    use warnings;

    use Data::Dumper;

    # Make Data::Dumper pretty
    $Data::Dumper::Sortkeys = 1;
    $Data::Dumper::Indent   = 1;

    # Set maximum depth for Data::Dumper, zero means unlimited
    local $Data::Dumper::Maxdepth = 0;

    my $string = '//google.com/Ucomm/Photos/1984 Digital Photos/blah blah/Reflections Magazine/Fall 1984    issue/This is what I want 7-28/TMI_7840_xx.PNG';

    my @array = split /\//, $string;
    print Dumper \@array;

__END__

Answer 5

您可以使用正则表达式：

if ($str=~/([^\/]*)\/([^\/]*)$/) {
   print "$1\n"
} else {
   print "ERROR\n"
}

示例：

perl -e '$str="google.com/Ucomm/Photos/1984 Digital Photos/blah blah/Reflections Magazine/Fall 1984    issue/This is what I want 7-28/TMI_7840_xx.PNG"; if ($str=~/([^\/]*)\/([^\/]*)$/) {print "$1\n"} else {print "ERROR\n"}'

This is what I want 7-28

如何打印一定数量的反斜杠之间的内容（Perl）

5 个答案: