How to convert XML into array in PHP?

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I want to convert below XML to PHP array. Any suggestions on how I can do this?

<aaaa Version="1.0">
   <bbb>
     <cccc>
       <dddd Id="id:pass" />
       <eeee name="hearaman" age="24" />
     </cccc>
   </bbb>
</aaaa>
11 Answers

The method used in the accepted answer drop attributes when encountering child elements with only a text node. For example:

$xml = '<container><element attribute="123">abcd</element></container>';
print_r(json_decode(json_encode(simplexml_load_string($xml, "SimpleXMLElement", LIBXML_NOCDATA)),1));

Array
(
    [element] => abcd
)

My solution (and I wish I could give credit here because I'm sure I adapted this from something):

function XMLtoArray($xml) {
    $previous_value = libxml_use_internal_errors(true);
    $dom = new DOMDocument('1.0', 'UTF-8');
    $dom->preserveWhiteSpace = false; 
    $dom->loadXml($xml);
    libxml_use_internal_errors($previous_value);
    if (libxml_get_errors()) {
        return [];
    }
    return DOMtoArray($dom);
}

function DOMtoArray($root) {
    $result = array();

    if ($root->hasAttributes()) {
        $attrs = $root->attributes;
        foreach ($attrs as $attr) {
            $result['@attributes'][$attr->name] = $attr->value;
        }
    }

    if ($root->hasChildNodes()) {
        $children = $root->childNodes;
        if ($children->length == 1) {
            $child = $children->item(0);
            if (in_array($child->nodeType,[XML_TEXT_NODE,XML_CDATA_SECTION_NODE])) {
                $result['_value'] = $child->nodeValue;
                return count($result) == 1
                    ? $result['_value']
                    : $result;
            }

        }
        $groups = array();
        foreach ($children as $child) {
            if (!isset($result[$child->nodeName])) {
                $result[$child->nodeName] = DOMtoArray($child);
            } else {
                if (!isset($groups[$child->nodeName])) {
                    $result[$child->nodeName] = array($result[$child->nodeName]);
                    $groups[$child->nodeName] = 1;
                }
                $result[$child->nodeName][] = DOMtoArray($child);
            }
        }
    }
    return $result;
}

$xml = '
    <aaaa Version="1.0">
       <bbb>
         <cccc>
           <dddd id="123" />
           <eeee name="john" age="24" />
           <ffff type="employee">Supervisor</ffff>
         </cccc>
       </bbb>
    </aaaa>
';
print_r(XMLtoArray($xml));

Array
(
    [aaaa] => Array
        (
            [@attributes] => Array
                (
                    [Version] => 1.0
                )

            [bbb] => Array
                (
                    [cccc] => Array
                        (
                            [dddd] => Array
                                (
                                    [@attributes] => Array
                                        (
                                            [id] => 123
                                        )

                                )

                            [eeee] => Array
                                (
                                    [@attributes] => Array
                                        (
                                            [name] => john
                                            [age] => 24
                                        )

                                )

                            [ffff] => Array
                                (
                                    [@attributes] => Array
                                        (
                                            [type] => employee
                                        )

                                    [_value] => Supervisor
                                )

                        )

                )

        )

)

I know I'm 1 billion years late, but I had the same problem as you and needed a more complex solution, so here is a function (xml_decode()) I made to convert SimpleXMLElements into PHP arrays without losing attributes and with arguments for a more customizable use.

The val() function is meant for you to customize how element values shall be treated - in case you want to transform <elem>true</elem> into true instead of "true" for example.

Disclaimer: I know it is easier to just use the PHP SimpleXML extension, but I needed to transform lots of XML files into JSON files for a big change in a project of mine. Also, the question is about how to transform XML to PHP arrays, not how to use XML in PHP.

<?php

function val($input) {
    return strval($input);
}

/**
 * Transform an SimpleXMLElement into an associative array.
 * 
 * @param SimpleXMLElement $xml The XML element to be decoded.
 * 
 * @param bool $attributes_key If the element attributes should be grouped into a single element.
 * 
 * Example: <elem foo="true" bar="false" />
 * 
 * If true, xml_decode() will output
 * array("attributes" => array("foo" => "true", "bar" => "false"))
 * 
 * If false, xml_decode() will output
 * array("foo" => "true", "bar" => "false")
 * 
 * @param bool $reduce If unecessary keys created due to XML structure should be eliminated.
 * 
 * Example: <fruits><fruit>apple</fruit><fruit>banana</fruit></fruits>
 * 
 * If true, xml_decode() will output the element as
 * array("fruits" => array(0 => "apple", 1 => "banana"))
 * 
 * If false, xml_decode() will output the element as
 * array("fruits" => array("fruit" => array(0 => "apple", 1 => "banana")))
 * 
 * @param array $always_array List of which childs should be treated aways as an array.
 * 
 * Example: <fruits><fruit>apple</fruit></fruits>
 * 
 * If array("fruit") is passed as $aways_array, xml_decode() will output the element as
 * array("fruits" => array("fruit" => array(0 => "apple")))
 * 
 * If not, xml_decode() will output the element as
 * array("fruits" => array("fruit" => "apple"))
 * 
 * @param array $value_keys List of custom element's value names. This argument is only
 * used when values need to passed as elements because of attributes or other reasons.
 * 
 * The default value key name is "value".
 * 
 * Example: <fruits><fruit id="123">apple</fruit></fruits>
 * 
 * If array("fruit" => "name) is passed as $value_keys, xml_decode() will output the element as
 * array("fruits" => array("fruit" => array("attributes" => array("id" => "123"), "name" => "apple")))
 * 
 * If not, xml_decode() will output the element as
 * array("fruits" => array("fruit" => array("attributes" => array("id" => "123"), "value" => "apple")))
 */
function xml_decode(SimpleXMLElement $xml, bool $attributes_key = true, bool $reduce = true,
    array $always_array = array(), array $value_keys = array()): string|array {

    // Inicialize the array.
    $arr = array();

    // XML tag name.
    $xml_name = $xml->getName();

    // Turn attributes into elements.
    foreach ($xml->attributes() as $key => $value) {
        // Use a key for attributes if $attributes_key argument is true.
        if ($attributes_key) {
            $arr['attributes'][val($key)] = val($value);
        } else {
            $arr[val($key)] = val($value);
        }
    }

    // Count children.
    $children_count = $xml->children()->count();

    // No children? Value will be text.
    if ($children_count == 0) {

        // If attributes were found and turned into elements
        // the value shall be an element.
        if (count($arr) > 0) {
            // If attributes were found previosly.
            $key = $value_keys[$xml_name] ?? $value_keys['*'] ?? "value";
            $arr[$key] = val($xml);
        // Else, no need for an array.
        } else {
            $arr = val($xml);
        }

    // Children? Loop continues.
    } else {

        // Defines if there are unecessary array keys - due to the XML structure - to be cut.
        // Example: <fruits><fruit /><fruit /><fruits />
        // could be turned into arr['fruits'][0] and arr['fruits'][1] instead of
        // arr['fruits']['fruit'][0] and arr['fruits']['fruit'][1] for a
        // cleaner organization.
        $children_names = array();
        foreach ($xml->children() as $child) {
            $child_name = $child->getName();
            in_array($child_name, $children_names) or $children_names[] = $child_name;
        }
        $reducible = empty($arr) && count($children_names) === 1;

        foreach ($xml->children() as $child) {

            // Child's name shall be the element key.
            $name = $child->getName();
            
            // Children with the same name will be turned into a list.
            // Example: $arr['repeating-child'][...] = $value;
            if ($xml->$name->count() > 1 || in_array($name, $always_array)) {

                // Reduction, if possible and requested by the $reduce argument.
                if ($reduce && $reducible) {
                    $arr[] = xml_decode($child, $attributes_key, $reduce, $always_array, $value_keys);
                } else {
                    $arr[$name][] = xml_decode($child, $attributes_key, $reduce, $always_array, $value_keys);
                }

            // Normal children will be normally decoded.
            // Example: $arr['no-repeating-child] = $value;
            } else {
                
                $arr[$name] = xml_decode($child, $attributes_key, $reduce, $always_array, $value_keys);

            }
        }
    }

    return $arr;

}

Resuming all the documentation and comments, the function transforms attributes and elements values into simple array elements and uses a loop with itself to process elements which contain children.

The arguments allow you to:

  • Group attributes into separate keys;
  • Cut unecessary keys generated due to the XML structure conversion (Example: fruits->fruit to $arr['fruits']['fruit'][n]);
  • Set elements which should aways be treated as lists (because sometimes it will have only one child element but you still need it to be a list);
  • Set a name for array element keys which will represent an XML element text value - which will be needed when attributes are converted to array elements.

Usage example with your XML elements (I think you already solved it after 11 years, but I'm answering it, so...):

test.xml

<test>
    <aaaa Version="1.0">
        <bbb>
            <cccc>
                <dddd Id="id:pass" />
                <eeee name="hearaman" age="24" />
            </cccc>
        </bbb>
    </aaaa>
</test>

PHP

$xml = simplexml_load_file("test.xml");
$decode = xml_decode($xml);
echo "<pre>" . print_r($decode,true) . "</pre>";

Output

Array
(
    [aaaa] => Array
        (
            [attributes] => Array
                (
                    [Version] => 1.0
                )

            [bbb] => Array
                (
                    [cccc] => Array
                        (
                            [dddd] => Array
                                (
                                    [attributes] => Array
                                        (
                                            [Id] => id:pass
                                        )

                                    [value] => 
                                )

                            [eeee] => Array
                                (
                                    [attributes] => Array
                                        (
                                            [name] => hearaman
                                            [age] => 24
                                        )

                                    [value] => 
                                )

                        )

                )

        )

)
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