使用XML :: LibXML在XML文档中的随机元素顺序

时间:2012-07-31 20:06:42

标签: perl csv xml-libxml

我有一个Perl脚本,可以读取如下所示的简单.csv文件 -

"header1","header2","header3","header4"
 "12","12-JUL-2012","Active","Processed"
 "13","11-JUL-2012","In Process","Pending"
 "32","10-JUL-2012","Active","Processed"
 "24","08-JUL-2012","Active","Processed"
 .....

目的是将此.csv转换为.xml文件,如下所示 -

<ORDERS>
  <LIST_G_ROWS>
     <G_ROWS>
         <header1>12</header1>
         <header2>12-JUL-2012</header2>
         <header3>Active</header3>
         <header4>Processed</header4>
     </G_ROWS>
     <G_ROWS>
         <header1>13</header1>
         <header2>11-JUL-2012</header2>
         <header3>In Process</header3>
         <header4>Pending</header4>
     </G_ROWS>
....
....
   </LIST_G_ROWS>
</ORDERS>

我知道CPAN中有XML::CSV可以让我的生活更轻松,但我想利用已安装的XML::LibXML来创建XML,而不是安装XML::CSV。我能够读取CSV并如上所述创建XML文件而没有任何问题,但我得到了XML中元素的随机顺序,如下所示。我需要让元素(子节点)的顺序与.csv文件同步,如上所示,但我不确定如何解决这个问题。我正在使用hashsort()哈希并没有完全解决问题。

<ORDERS>
  <LIST_G_ROWS>
     <G_ROWS>
         <header3>Active</header3>
         <header1>12</header1>
         <header4>Processed</header4>
         <header2>12-JUL-2012</header2>                          
     </G_ROWS>
 ......

等等。以下是我的perl代码的片段

use XML::LibXML;
use strict;

my $outcsv="/path/to/data.csv";
my $$xmlFile="/path/to/data.xml";
my $headers = 0;
my $doc = XML::LibXML::Document->new('1.0', 'UTF-8');
my $root = $doc->createElement("ORDERS");
my $list = $doc->createElement("LIST_G_ROWS");
$root->appendChild($list);

open(IN,"$outcsv") || die "can not open $outcsv:  $!\n";
while(<IN>){    
    chomp($_);
    if ($headers == 0)
    {
        $_ =~ s/^\"//g;     #remove starting (")
        $_ =~ s/\"$//g;     #remove trailing (")
        @keys = split(/\",\"/,$_);  #split per ","
        s{^\s+|\s+$}{}g foreach @keys;  #remove leading and trailing spaces from each field
        $headers = 1;       
    }
    else{   
        $_ =~ s/^\"//g;     #remove starting (")
        $_ =~ s/\"$//g;     #remove trailing (")    
        @vals = split(/\",\"/,$_);  #split per ","
        s{^\s+|\s+$}{}g foreach @vals;  #remove leading and trailing spaces from each field

        my %tags = map {$keys[$_] => $vals[$_]} (0..@keys-1);                   
        my $row  = $doc->createElement("G_ROWS");
        $list->appendChild($row);
        for my $name (keys %tags) {
            my $tag = $doc->createElement($name);
            my $value = $tags{$name};
            $tag->appendTextNode($value);               
            $row->appendChild($tag);
        }
    }
}
close(IN);

$doc->setDocumentElement($root);
open(OUT,">$xmlFile") || die "can not open $xmlFile:  $!\n";
print OUT $doc->toString();
close(OUT);

3 个答案:

答案 0 :(得分:1)

你可以完全忘记%tags哈希。相反,循环遍历@keys

的索引
for my $i (0 .. @keys - 1) {
    my $key   = $keys[$i];
    my $value = $values[$i];
    my $tag   = $doc->createElement($key);
    $tag->appendTextNode($value);
    $row->appendChild($tag);
}

这样,您的密钥的排序就会被保留。使用哈希时,排序是不确定的。

答案 1 :(得分:1)

您的计划涉及的程度远远超过其需要。为方便和可靠,您应使用Text::CSV来解析CSV文件。

以下程序可以满足您的需求。

use strict;
use warnings;

use Text::CSV;
use XML::LibXML;

open my $csv_fh, '<', '/path/to/data.csv' or die $!;
my $csv = Text::CSV->new;
my $headers = $csv->getline($csv_fh);

my $doc = XML::LibXML::Document->new('1.0', 'UTF-8');
my $orders = $doc->createElement('ORDERS');
$doc->setDocumentElement($orders);
my $list = $orders->appendChild($doc->createElement('LIST_G_ROWS'));

while ( my $data = $csv->getline($csv_fh) ) {

  my $rows = $list->appendChild($doc->createElement('G_ROWS'));

  for my $i (0 .. $#$data) {
    $rows->appendTextChild($headers->[$i], $data->[$i]);
  }
}

print $doc->toFile('/path/to/data.xml', 1);

<强>输出

<?xml version="1.0" encoding="UTF-8"?>
<ORDERS>
  <LIST_G_ROWS>
    <G_ROWS>
      <header1>12</header1>
      <header2>12-JUL-2012</header2>
      <header3>Active</header3>
      <header4>Processed</header4>
    </G_ROWS>
    <G_ROWS>
      <header1>13</header1>
      <header2>11-JUL-2012</header2>
      <header3>In Process</header3>
      <header4>Pending</header4>
    </G_ROWS>
    <G_ROWS>
      <header1>32</header1>
      <header2>10-JUL-2012</header2>
      <header3>Active</header3>
      <header4>Processed</header4>
    </G_ROWS>
    <G_ROWS>
      <header1>24</header1>
      <header2>08-JUL-2012</header2>
      <header3>Active</header3>
      <header4>Processed</header4>
    </G_ROWS>
  </LIST_G_ROWS>
</ORDERS>

<强>更新

如果没有Text::CSV提供的奇特选项,如果其选项已修复,其功能相当简单。此备选方案提供了子例程csv_readline来替换Text::CSV方法readline。它的工作方式与模块大致相同。

该程序的输出与上述相同。

use strict;
use warnings;

use XML::LibXML;

open my $csv_fh, '<', '/path/to/data.csv' or die $!;

my $doc = XML::LibXML::Document->new('1.0', 'UTF-8');
my $orders = $doc->createElement('ORDERS');
$doc->setDocumentElement($orders);
my $list = $orders->appendChild($doc->createElement('LIST_G_ROWS'));

my $headers = csv_getline($csv_fh);

while ( my $data = csv_getline($csv_fh) ) {

  my $rows = $list->appendChild($doc->createElement('G_ROWS'));

  for my $i (0 .. $#$data) {
    $rows->appendTextChild($headers->[$i], $data->[$i]);
  }
}

print $doc->toFile('/path/to/data.xml', 1);

sub csv_getline {
  my $fh = shift;
  defined (my $line = <$fh>) or return;
  $line =~ s/\s*\z/,/;
  [ map { /"(.*)"/ ? $1 : $_ } $line =~ /( " [^"]* " | [^,]* ) , /gx ];
}

答案 2 :(得分:-2)

似乎XML::LibXml有点过分,只需使用XML::Simple并构建描述该XML结构的正确哈希,而不是将XMLOut转储到XML文件< / p>