如何提取和轉換XML到Perl數據結構

Question

我有一個文件夾中的XML文件，我需要提取從XML文件和存儲的一些信息在hash.My XML文件看起來像這樣

<?xml version="1.0" encoding="UTF-8"?> 
<Servicemodule xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
<Service Id="478" Name="Pump Motor"> 
<Description>It delivers actual pump speed</Description> 
<ServiceCustomers> 
    <SW Service="SKRM" Path="/work/hr_service.xml"/> 
</ServiceCustomers> 
<ServiceSuppliers> 
    <HW Type="s" Nr="12" Service="1" Path="/work/hardware.xml"/> 
    <HW Type="v" Nr="2" Service="1" Path="/work/hardware.xml"/> 
    <HW Type="mt" Nr="1" Service="1" Path="/work/hardware.xml"/> 
</ServiceSuppliers> 
</Service> 
</Servicemodule> 

我想將這些信息保存在一個像服務Id這樣的散列中，作爲密鑰和擴展信息作爲該密鑰的散列值數組。服務客戶和供應商元素中的軟件和硬件屬性都是散列鍵值（服務ID）的數組值。它對於專家來說很容易，但我是新學習者，所以這個問題讓我苦惱。 我試過這樣

use strict; 
use warnings; 
use feature ':5.10'; 
use XML::Twig; 
use File::Find; 

my $num=0; 
my %combeh; 
my $dir="V:/Main/work"; 
find(\&wanted, $dir); 
sub wanted() { 
    if (-f and /(_service\.xml)$/) {# find all the files with a suffix of .xml           
my $tweak_server =sub{ 
       my @bhi;                      
    my ($twig, $root) =@_;                      
    my $code=$root->first_child_text('Service Id');                     
    my $ser=$root->first_child('ServiceCustomers');                      
    my $ser_cnt=$root->first_child_text('SW'); 
    my $ser1=$root->first_child('ServiceSuppliers');                      
    my $ser1_cnt=$root->first_child_text('HW');                      
    if ($ser){                              
    push (@bhi, $ser->toString,$File::Find::name);                              
     $combeh{$code}=[@bhi]; 
     } 
     if ($ser1){                              
    push (@bhi, $ser1->toString,$File::Find::name);                              
     $combeh{$code}=[@bhi];   
      }; 
     my $roots = { Service => 1 }; 
    my $handlers = { 'Servicemodule/Service' => $tweak_server,                                            
         }; 
     my $twig = new XML::Twig(TwigRoots => $roots,                                                   
          TwigHandlers => $handlers,                                                   
           pretty_print => 'indented'                                            
           ); 
       $twig->parsefile($_);                      
          }      
         } 
       return (%combeh) ; 
       } 

我不能用，因爲我想用上面的腳本創建哈希值。請幫我看看劇本如何讓一個哈希的屬性值和存儲這樣 出認沽需要這項

'478'=>[ 
      { 
      Description='It delivers actual pump speed' 
      } 
     { 
      Service='SKRM', 
      Path='/work/hr_service.xml' 
      } 
      { 
      Type='s'. 
      Nr='12', 
      Service='s', 
      path='/work/hardware.xml' 
      } 

      { 
      Type='v'. 
      Nr='2', 
      Service='s', 
      path='/work/hardware.xml' 
      } 
      { 
      Type='mt'. 
      Nr='1', 
      Service='1', 
      path='/work/hardware.xml' 
      } 
     ... 
      ... 
      .... 

請幫我解決這個問題。

在此先感謝。

我想你這樣的建議後

#!/usr/bin/perl 
use warnings; 
use strict; 
use XML::Simple; 
use Carp; 
use File::Find; 
use File::Spec::Functions qw(canonpath);  
use Data::Dumper; 

my @ARGV ="C:/Main/work";die "Need directories\n" unless @ARGV; 
find(
    sub { 
    return unless (/(_service\.xml)$/ and -f); 
    extract_information(); 
    return; 
    }, 
@ARGV 
); 

sub extract_information { 
     my $path= $_; 

my $xml=XMLin($path); 
    my $xml_services = $xml->{Service}; 
    my %services; 
    for my $xml_service (@$xml_services) { 

    my %service = (
     description  => $xml_service->{Description}, 
     name   => $xml_service->{Name}, 
     id    => $xml_service->{Id}, 
    ); 

    $service{sw} = _maybe_list($xml_service->{ServiceCustomers}{SW}); 
    $service{hw} = _maybe_list($xml_service->{ServiceSuppliers}{HW}); 
    $service{sw} = _maybe_list($xml_service->{ServiceSuppliers}{SW}); 
    $services{ $service{id} } = \%service; 
} 

print Dumper \%services; 

    } 
sub _maybe_list { 
my $maybe = shift; 
return ref $maybe eq 'ARRAY' ? $maybe : [$maybe]; 
} 

感謝您的回覆，我是新來的XML ::簡單，我研究了模塊和我理解你的腳本。但是當我運行你的代碼時，我得到了錯誤，如「不是數組引用」for循環line.I嘗試以不同的方式來克服這一點，但仍然是相同的錯誤。有時我在ServiceSuppliers中有SW和HW屬性。所以我再添加一行與你的格式相同。我有一個問題，你說：「如果XML中有單個元素，它將不會被包裹」，但有時在ServiceCustomers中，我只有一個元素，像我在xml文件中顯示的那樣具有一些屬性。是否可以？或者我應該怎麼做？你能幫我解決這些問題嗎？

請任何人幫我解決這個錯誤。

Answer 1

如果XML文件不是太大，可以使用XML::Simple更容易地轉換它。

XML :: Simple的優點是操作Perl數據結構比XML更方便。

缺點是它會消耗更多的內存，因爲它必須將整個XML文件加載到內存中。它對XML中的外殼也很敏感。

use strict; 
use warnings; 

use XML::Simple; 
use Data::Dumper; 

process_service_xml(shift); 

sub process_service_xml { 
    my $xml = XMLin(shift); 

    # Illustrating what you've got after XML::Simple processes it. 
    print "******* XML::Simple input ********\n"; 
    print Dumper $xml; 
    print "**********************************\n"; 

    # Pull out the Services 
    my $xml_services = $xml->{Service}; 

    # Iterate through each Service to transform them 
    my %services; 
    for my $xml_service (@$xml_services) { 
     # Pull out the basic information 
     my %service = (
      description  => $xml_service->{Description}, 
      name   => $xml_service->{Name}, 

      # Redundant with the key, but useful to keep all the data about the 
      # service in one place. 
      id    => $xml_service->{Id}, 
     ); 

     # Get SW and HW as their own attributes. 
     # If there's a single element in the XML it won't be wrapped in 
     # an array, so make sure each are a list. 
     $service{sw} = _maybe_list($xml_service->{ServiceCustomers}{SW}); 
     $service{hw} = _maybe_list($xml_service->{ServiceSuppliers}{HW}); 

     # Store the service in the larger hash, keyed by the ID. 
     $services{ $service{id} } = \%service; 
    } 

    # And here's what the information has been transformed into. 
    print "******* Services ********\n"; 
    print Dumper \%services; 
    print "*************************\n";  
} 

sub _maybe_list { 
    my $maybe = shift; 
    return ref $maybe eq 'ARRAY' ? $maybe : [$maybe]; 
}