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XML::SimpleObject::LibXML.3pm

NAME

XML::SimpleObject::LibXML - Perl extension allowing a simple(r) object representation of an XML::LibXML DOM object.

SYNOPSIS

   use XML::SimpleObject::LibXML;
 
   # Construct with the key/value pairs as argument; this will create its 
   # own XML::LibXML object.
   my $xmlobj = new XML::SimpleObject(XML => $XML);
 
   # ... or construct with the parsed tree as the only argument, having to 
   # create the XML::Parser object separately.
   my $parser = new XML::LibXML;
   my $dom    = $parser->parse_file($file); # or $parser->parse_string($xml);
   my $xmlobj = new XML::SimpleObject::LibXML ($dom);
 
   my $filesobj = $xmlobj->child("files")->child("file");
 
   $filesobj->name;
   $filesobj->value;
   $filesobj->attribute("type");
   
   %attributes    = $filesobj->attributes;
   @children      = $filesobj->children;
   @some_children = $filesobj->children("some");
   @children_names = $filesobj->children_names;
 
 

DESCRIPTION

This is a short and simple class allowing simple object access to a parsed XML::LibXML tree, with methods for fetching children and attributes in as clean a manner as possible. My apologies for further polluting the XML:: space; this is a small and quick module, with easy and compact usage. Some will rightfully question placing another interface over the DOM methods provided by XML::LibXML, but my experience is that people appreciate the total simplicity provided by this module, despite its limitations.

USAGE

$xmlobj = new XML::SimpleObject::LibXML($parser->parse_string($XML))

$parser is an XML::LibXML object.

After creating $xmlobj, this object can now be used to browse the XML tree with the following methods.

$xmlobj->child('NAME')

This will return a new XML::SimpleObject::LibXML object using the child element NAME.

$xmlobj->children('NAME')

Called with an argument NAME, children() will return an array of XML::SimpleObject::LibXML objects of element NAME. Thus, if $xmlobj represents the top-level XML element, 'children' will return an array of all elements directly below the top-level that have the element name NAME.

$xmlobj->children

Called without arguments, 'children()' will return an array of XML::SimpleObjects::LibXML objects for all children elements of $xmlobj. Unlike XML::SimpleObject, XML::SimpleObject::LibXML retains the order of these children.

$xmlobj->children_names

This will return an array of all the names of child elements for $xmlobj. You can use this to step through all the children of a given element (see EXAMPLES), although multiple elements of the same name will not be identified. Use 'children()' instead.

$xmlobj->value

If the element represented by $xmlobj contains any PCDATA, this method will return that text data.

$xmlobj->attribute('NAME')

This returns the text for an attribute NAME of the XML element represented by $xmlobj.

$xmlobj->attributes

This returns a hash of key/value pairs for all elements in element $xmlobj.

EXAMPLES

Given this XML document:

   <files>
     <file type="symlink">
       <name>/etc/dosemu.conf</name>
       <dest>dosemu.conf-drdos703.eval</dest>
     </file>
     <file>
       <name>/etc/passwd</name>
       <bytes>948</bytes>
     </file>
   </files>
 
 

You can then interpret the tree as follows:

   my $parser = new XML::LibXML;
   my $xmlobj = new XML::SimpleObject::LibXML ($parser->parse_string($XML));
 
   print "Files: \n";
   foreach my $element ($xmlobj->child("files")->children("file"))
   {
     print "  filename: " . $element->child("name")->value . "\n";
     if ($element->attribute("type"))
     {
       print "    type: " . $element->attribute("type") . "\n";
     }
     print "    bytes: " . $element->child("bytes")->value . "\n";
   }
 
 

This will output:

   Files:
     filename: /etc/dosemu.conf
       type: symlink
       bytes: 20
     filename: /etc/passwd
       bytes: 948
 
 

You can use 'children()' without arguments to step through all children of a given element:

   my $filesobj = $xmlobj->child("files")->child("file");
   foreach my $child ($filesobj->children) {
     print "child: ", $child->name, ": ", $child->value, "\n";
   }
 
 

For the tree above, this will output:

   child: bytes: 20
   child: dest: dosemu.conf-drdos703.eval
   child: name: /etc/dosemu.conf
 
 

Using 'children_names()', you can step through all children for a given element:

   my $filesobj = $xmlobj->child("files");
   foreach my $childname ($filesobj->children_names) {
       print "$childname has children: ";
       print join (", ", $filesobj->child($childname)->children_names), "\n";
   }
 
 

This will print:

     file has children: bytes, dest, name
 
 

By always using 'children()', you can step through each child object, retrieving them with 'child()'.

AUTHOR

Dan Brian <dan@brians.org>

SEE ALSO

perl(1), XML::SimpleObject, XML::Parser, XML::LibXML.