将新节点/元素添加到XML :: LibXML对象

Question

这是一个基本的XML文档示例

<book_reviewers>
    <results>
        <reviewer>
            <name>Anne</name>
            <profession>Catfish wrangler</profession>
        </reviewer>
        <reviewer>
            <name>Bob</name>
            <profession>Beer taster</profession>
        </reviewer>
        <reviewer>
            <name>Charlie</name>
            <profession>Gardener</profession>
        </reviewer>
    </results>
</book_reviewers>

我想补充一点：

<reviewer>
    <name>Joan</name>
    <profession>Jett</profession>
 </reviewer>

我尝试过多种解决方案的组合，这里至少不会产生错误，但是，它也不起作用。

#!/usr/bin/perl
use XML::LibXML;
use strict;

my $filename = "cr.xml";

my $parser = XML::LibXML->new();
my $critic_details = $parser->parse_file("$filename") or die;
my $new_reviewer = $critic_details->documentElement;
my $reviewer_name = $critic_details->documentElement;
my $reviewer_prof = $critic_details->documentElement;
my $newnode = $critic_details->documentElement;

 for my $reviewers($critic_details->findnodes("book_reviewers/results/reviewers")){
     $new_reviewer = $reviewers->createElement("reviewer");
    $reviewer_name = $new_reviewer->addChild("name");
    $reviewer_name->appendText("Joan");
    $reviewer_prof = $new_reviewer->addChild("profession");
    $reviewer_prof->appendText("Jett");
    $newnode = $reviewers->addSibling($new_reviewer); #also tried addChild

}
print $critic_details->toString;

我得到的输出是：

<?xml version="1.0"?>
<book_reviewers>
        <results>
                <reviewer>
                        <name>Anne</name>
                        <profession>Catfish wrangler</profession>
                </reviewer>
                <reviewer>
                        <name>Bob</name>
                        <profession>Beer taster</profession>
                </reviewer>
                <reviewer>
                        <name>Charlie</name>
                        <profession>Gardener</profession>
                </reviewer>
        </results>
</book_reviewers>

这只是原始数据

任何帮助都非常感激 - 我对Perl和XML都很新 干杯

Answer 1

只是为了帮助你解决XML::LibXML更整洁的事情并让你更容易理解XML是如何工作的，我在这里发布了另一个答案。也许你会在其中找到一些有用的线索：

use strict;
use warnings;

use utf8;

use XML::LibXML;

my $filename = "cr.xml";

my $parser = XML::LibXML->new();
my $critic_details = $parser->parse_file("$filename") or die;

# find ALL the <book_reviewers><results> nodes
my @results = $critic_details->findnodes("book_reviewers/results");
die "no result node in xml-file" unless @results;

my ($name, $profession) = ("Joan", "Jett");

#
# Here gets the work done, put this in a loop for more entries
#

# add a new <reviewer> node to the LAST <results>
my $reviewer_node_child;
my $reviewer_node = $results[-1]->addNewChild(undef, "reviewer");

# create a child node
$reviewer_node_child =  $reviewer_node->addNewChild(undef, "name");
$reviewer_node_child->appendTextNode($name);

# create a child node
$reviewer_node_child =  $reviewer_node->addNewChild(undef, "profession");
$reviewer_node_child->appendTextNode($profession);

#
# Done the heavy power lifting
#

use XML::LibXML::PrettyPrint;
my $pretty = XML::LibXML::PrettyPrint->new(
  indent_string => ' ' x4,
  element       => {
    compact       => [qw| name profession | ],
    }
  );
$pretty->pretty_print($critic_details);

print $critic_details->toString;

__END__

此处需要undef方法中的addNewChild。它们用于设置XML-NameSpace，这里不需要它，但是在大型XML文档中真的是要走的路。

另外，我添加XML::LibXML::PrettyPrint只是为了向您展示如何回到漂亮漂亮的语法。请原谅我添加use…添加脚本的结尾。

产生这个结果：

<?xml version="1.0"?>
<book_reviewers>
    <results>
        <reviewer>
            <name>Anne</name>
            <profession>Catfish wrangler</profession>
        </reviewer>
        <reviewer>
            <name>Bob</name>
            <profession>Beer taster</profession>
        </reviewer>
        <reviewer>
            <name>Charlie</name>
            <profession>Gardener</profession>
        </reviewer>
        <reviewer>
            <name>Joan</name>
            <profession>Jett</profession>
        </reviewer>
    </results>
</book_reviewers>

享受XML和Perl，这是一个非常强大但令人生畏的工具组合！

Answer 2

有很多方法可以做到这一点

这种方式分别创建节点并将它们放在一起。这不是生产准备，因为它假设有一个部分

#!/usr/bin/perl
use XML::LibXML;
use strict;

my $filename = "cr.xml";

my $parser = XML::LibXML->new();
my $critic_details = $parser->parse_file("$filename") or die;

my $reviewer  = $critic_details->findnodes("book_reviewers/results")->[0];

my $node = XML::LibXML::Element->new("reviewer");

my $p = XML::LibXML::Element->new("profession");
my $pn = XML::LibXML::Text->new("Jett");
$p->addChild($pn);

my $n = XML::LibXML::Element->new("name");
my $nn = XML::LibXML::Text->new("Joan");
$n->addChild($nn);

$node->addChild($p);
$node->addChild($n);

$reviewer->addChild($node);

print $critic_details->toString;

给出了这个

<?xml version="1.0"?>
<book_reviewers>
    <results>
        <reviewer>
            <name>Anne</name>
            <profession>Catfish wrangler</profession>
        </reviewer>
        <reviewer>
            <name>Bob</name>
            <profession>Beer taster</profession>
        </reviewer>
        <reviewer>
            <name>Charlie</name>
            <profession>Gardener</profession>
        </reviewer>
    <reviewer><profession>Jett</profession><name>Joan</name></reviewer></results>
</book_reviewers>

Answer 3

可以使用XML::LibXML将节点从一个XML文档导入另一个XML文档。这很有用，因为您不必使用对象显式构建新数据，而只能使用标准XML表示法。

以下说明了这一点。通过在新文档中设置根节点然后迭代找到的节点而不是仅选择第一个节点，可以轻松地将其扩展为重要的多个新审阅者。

#!/usr/bin/perl

use strict;
use warnings;

use XML::LibXML;

my $dom = XML::LibXML->load_xml(IO => \*DATA);

my $newnode = XML::LibXML->load_xml(string => <<'END_STRING')->findnodes('//*')->[0];
<reviewer>
    <name>Joan</name>
    <profession>Jett</profession>
</reviewer>
END_STRING

$dom->findnodes("book_reviewers/results")->[0]->addChild($newnode);

print $dom->toString;

__DATA__
<book_reviewers>
    <results>
        <reviewer>
            <name>Anne</name>
            <profession>Catfish wrangler</profession>
        </reviewer>
        <reviewer>
            <name>Bob</name>
            <profession>Beer taster</profession>
        </reviewer>
        <reviewer>
            <name>Charlie</name>
            <profession>Gardener</profession>
        </reviewer>
    </results>
</book_reviewers>

输出：

<?xml version="1.0"?>
<book_reviewers>
    <results>
        <reviewer>
            <name>Anne</name>
            <profession>Catfish wrangler</profession>
        </reviewer>
        <reviewer>
            <name>Bob</name>
            <profession>Beer taster</profession>
        </reviewer>
        <reviewer>
            <name>Charlie</name>
            <profession>Gardener</profession>
        </reviewer>
    <reviewer>
    <name>Joan</name>
    <profession>Jett</profession>
</reviewer></results>
</book_reviewers>