In you care about the order of those elements XML::Simple (or indeed any similar XML-to-hashref tool) is not your friend. Perl hashes do not preserve order. There are modules that give you order-preserving hashes (via ties) but persuading XML::Simple to use them is probably not possible.

use PerlX::MethodCallWithBlock;
use Text::CSV;
use XML::LibXML 1.94;

local $\ = "\n";
my $xml  = XML::LibXML->load_xml(IO => \*DATA);
my $csv  = Text::CSV->new;

foreach my $book ($xml->findnodes('/library/book'))
{
    my $row = $book->findnodes('./*')->map{ $_->textContent };
    $csv->print(\*STDOUT, $row);
}

__DATA__
<library>
    <book>
        <author>Book 1 author 1</author>
        <author>Book 1 author 2</author>
        <title>Book 1 title</title>
        <isbn>Book1ISBN</isbn>
    </book>
    <book>
        <author>Book 2 author 1</author>
        <author>Book 2 author 2</author>
        <title>Book 2 title</title>
        <isbn>Book2ISBN</isbn>
    </book>
</library>

[download]

The output from the above is:

"Book 1 author 1","Book 1 author 2","Book 1 title",Book1ISBN
"Book 2 author 1","Book 2 author 2","Book 2 title",Book2ISBN
perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

In reply to Re: How to use perl to parsing a XML file to csv file which have the same sequence in xml file? by tobyink
in thread How to use perl to parsing a XML file to csv file which have the same sequence in xml file? by carol.j

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