Beginning Web Development With Perl : From Novice to ... - Nabo

CHAPTER 9 ■ XML PARSING WITH PERL 171The code reads in the XML with the forcearray option enabled. Each value is then accessedthrough its dereferenced array index. The exception is the element, which may be multivalued.The element is printed by using an array reference to that specific element.Since four of the five elements in this XML data structure can have only one value, youmay want to specify which elements should go into an array, instead of rolling every elementinto an array. Instead of merely accepting 1 for enabled and 0 for disabled, the forcearrayoption can accept a comma-separated list of elements that should be rolled into an array.Continuing with the previous example, using forcearray just for the elementlooks like this:#!/usr/bin/perluse strict;use XML::Simple;my $xml = XMLin('./xml_example2',forcearray=> [ 'vehicle' ]);foreach my $customer (@{$xml->{customer}}) {print "Name: $customer->{first_name} ";print "$customer->{last_name}\n";print "Birthday: $customer->{dob}\n";print "E-mail Address: $customer->{email}\n";print "Vehicle(s): @{$customer->{vehicle}}\n";}Notice in this example that the array index ->[0] is now gone for the original four elements,since those are no longer rolled into an array by XML::Simple.KeyAttrThe KeyAttr option is used to control how elements are rolled into arrays and hashes. Recallan earlier example showing an XML structure as displayed with Data::Dumper. Changing thekey attribute to be the element reveals this output:$VAR1 = {'customer' => {'frank@example.com' => {'dob' => '3/10','first_name' => 'Frank','last_name' => 'Sanbeans'},'sandy@example.com' => {'dob' => '4/15','first_name' => 'Sandy','last_name' => 'Sanbeans'}}};