iterating over unknown XML structure with PHP (DOM)

Question

Hi all I want to write a function that parses a (theoretically) unknown XML data structure into an equivalent PHP array.

Here is my sample XML:

<?xml version="1.0" encoding="UTF-8"?>
<content>

<title>Sample Text</title>

<introduction>
    <paragraph>This is some rudimentary text</paragraph>
</introduction>
<description>
    <paragraph>Here is some more text</paragraph>
    <paragraph>Even MORE text</paragraph>
    <sub_section>
        <sub_para>This is a smaller, sub paragraph</sub_para>
        <sub_para>This is another smaller, sub paragraph</sub_para>
    </sub_section>
</description>
</content>

I modified this DOM iterating function from devarticles:

$data = 'path/to/xmldoc.xml';
$xmlDoc = new DOMDocument(); #create a DOM element
$xmlDoc->load( $data ); #load data into the element
$xmlRoot = $xmlDoc->firstChild; #establish root

function xml2array($node)
    {
    if ($node->hasChildNodes())
    {
$subNodes = $node->childNodes;
    foreach ($subNodes as $subNode)
        {
        #filter node types
        if (($subNode->nodeType != 3) || (($subNode->nodeType == 3)))   
            {
            $arraydata[$subNode->nodeName]=$subNode->nodeValue;
            }
         xml2array($subNode);
         }
      }
      return $arraydata;
   }
//The getNodesInfo function call

 $xmlarray = xml2array($xmlRoot);


// print the output - with a little bit of formatting for ease of use...
foreach($xmlarray as $xkey)
     {
     echo"$xkey<br/><br/>";
     }

Now, because of the way I'm passing the elements to the array I'm overwriting any elements that share a node name (since I ideally want to give the keys the same names as their originating nodes). My recursion isn't great... However, even if I empty the brackets - the second tier of nodes are still coming in as values on the first tier (see the text of the description node).

Anyone got any ideas how I can better construct this?

Answer 1

You might be better off just snagging some code off the net

http://www.bin-co.com/php/scripts/xml2array/

 /**
  * xml2array() will convert the given XML text to an array in the XML structure.
  * Link: http://www.bin-co.com/php/scripts/xml2array/
  * Arguments : $contents - The XML text
  *                $get_attributes - 1 or 0. If this is 1 the function will get the attributes as well as the tag values - this results in a different array structure in the return value.
  *                $priority - Can be 'tag' or 'attribute'. This will change the way the resulting array sturcture. For 'tag', the tags are given more importance.
  * Return: The parsed XML in an array form. Use print_r() to see the resulting array structure.
  * Examples: $array =  xml2array(file_get_contents('feed.xml'));
  *              $array =  xml2array(file_get_contents('feed.xml', 1, 'attribute'));
  */
 function xml2array($contents, $get_attributes=1, $priority = 'tag') {

Answer 2

You might be interested in SimpleXML or xml_parse_into_struct.

$arraydata is neither passed to subsequent calls to xml2array() nor is the return value used, so yes "My recursion isn't great..." is true ;-)
To append a new element to an existing array you can use empty square brackets, $arr[] = 123; $arr[$x][] = 123;

Answer 3

You might also want to check out XML Unserializer

http://pear.php.net/package/XML_Serializer/redirected