How to convert array to SimpleXML

Question

How can I convert an array to a SimpleXML object in PHP?

Answer 1

Just a edit on a function above, when a key is numeric, add a prefix "key_"

// initializing or creating array
$student_info = array(your array data);

// creating object of SimpleXMLElement
$xml_student_info = new SimpleXMLElement("<?xml version=\"1.0\"?><student_info></student_info>");

// function call to convert array to xml
array_to_xml($student,$xml_student_info);

//saving generated xml file
$xml_student_info->asXML('file path and name');


function array_to_xml($student_info, &$xml_student_info) {
     foreach($student_info as $key => $value) {
          if(is_array($value)) {
            if(!is_numeric($key)){
                $subnode = $xml_student_info->addChild("$key");
                array_to_xml($value, $subnode);
            }
            else{
                $subnode = $xml_student_info->addChild("key_$key");
                array_to_xml($value, $subnode);
            }
          }
          else {
               if(!is_numeric($key)){
                    $xml_student_info->addChild("$key","$value");
               }else{
                    $xml_student_info->addChild("key_$key","$value");
               }
          }
     }
}

Answer 2

I found all of the answers to use too much code. Here is an easy way to do it:

function to_xml(SimpleXMLElement $object, array $data)
{   
    foreach ($data as $key => $value) {
        if (is_array($value)) {
            $new_object = $object->addChild($key);
            to_xml($new_object, $value);
        } else {
            // if the key is an integer, it needs text with it to actually work.
            if ($key == (int) $key) {
                $key = "key_$key";
            }

            $object->addChild($key, $value);
        }   
    }   
}   

Then it's a simple matter of sending the array into the function, which uses recursion, so it will handle a multi-dimensional array:

$xml = new SimpleXMLElement('<rootTag/>');
to_xml($xml, $my_array);

Now $xml contains a beautiful XML object based on your array exactly how you wrote it.

print $xml->asXML();

Answer 3

I use a couple of functions that I wrote a while back to generate the xml to pass back and forth from PHP and jQuery etc... Neither use any additional frameworks just purely generates a string that can then be used with SimpleXML (or other framework)...

If it's useful to anyone, please use it :)

function generateXML($tag_in,$value_in="",$attribute_in=""){
    $return = "";
    $attributes_out = "";
    if (is_array($attribute_in)){
        if (count($attribute_in) != 0){
            foreach($attribute_in as $k=>$v):
                $attributes_out .= " ".$k."=\"".$v."\"";
            endforeach;
        }
    }
    return "<".$tag_in."".$attributes_out.((trim($value_in) == "") ? "/>" : ">".$value_in."</".$tag_in.">" );
}

function arrayToXML($array_in){
    $return = "";
    $attributes = array();
    foreach($array_in as $k=>$v):
        if ($k[0] == "@"){
            // attribute...
            $attributes[str_replace("@","",$k)] = $v;
        } else {
            if (is_array($v)){
                $return .= generateXML($k,arrayToXML($v),$attributes);
                $attributes = array();
            } else if (is_bool($v)) {
                $return .= generateXML($k,(($v==true)? "true" : "false"),$attributes);
                $attributes = array();
            } else {
                $return .= generateXML($k,$v,$attributes);
                $attributes = array();
            }
        }
    endforeach;
    return $return;
}   

Love to all :)

Answer 4

Most of the above answers are correct. However, I came up with this answer which solves the array_walk_recursive compatibility issue and also the numerical keys problem. It also passed all the tests I made:

function arrayToXML(Array $array, SimpleXMLElement &$xml) {

    foreach($array as $key => $value) {

        // None array
        if (!is_array($value)) {
            (is_numeric($key)) ? $xml->addChild("item$key", $value) : $xml->addChild($key, $value);
            continue;
        }   

        // Array
        $xmlChild = (is_numeric($key)) ? $xml->addChild("item$key") : $xml->addChild($key);
        arrayToXML($value, $xmlChild);
    }
}   

I have also added a test class for this which you may find useful:

class ArrayToXmlTest extends PHPUnit_Framework_TestCase {

    public function setUp(){ }
    public function tearDown(){ }

    public function testFuncExists() {
        $this->assertTrue(function_exists('arrayToXML'));
    }

    public function testFuncReturnsXml() {
        $array = array(
            'name' => 'ardi',
            'last_name' => 'eshghi',
            'age' => 31,
            'tel' => '0785323435'
        );

        $xmlEl =  new SimpleXMLElement('<root/>');
        arrayToXml($array, $xmlEl);

        $this->assertTrue($xmlEl instanceOf SimpleXMLElement);
    }

    public function testAssocArrayToXml() {

        $array = array(
            'name' => 'ardi',
            'last_name' => 'eshghi',
            'age' => 31,
            'tel' => '0785323435'
        );

        $expectedXmlEl = new SimpleXMLElement('<root/>'); 
        $expectedXmlEl->addChild('name', $array['name']);
        $expectedXmlEl->addChild('last_name', $array['last_name']);
        $expectedXmlEl->addChild('age', $array['age']);
        $expectedXmlEl->addChild('tel', $array['tel']);

        $actualXmlEl =  new SimpleXMLElement('<root/>');
        arrayToXml($array, $actualXmlEl);

        $this->assertEquals($expectedXmlEl->asXML(), $actualXmlEl->asXML());
    }

    public function testNoneAssocArrayToXml() {

        $array = array(
            'ardi',
            'eshghi',
            31,
            '0785323435'
        );

        // Expected xml value
        $expectedXmlEl = new SimpleXMLElement('<root/>'); 
        foreach($array as $key => $value)
            $expectedXmlEl->addChild("item$key", $value);

        // What the function produces       
        $actualXmlEl =  new SimpleXMLElement('<root/>');
        arrayToXml($array, $actualXmlEl);

        $this->assertEquals($expectedXmlEl->asXML(), $actualXmlEl->asXML());
    }

    public function testNestedMixArrayToXml() {

        $testArray = array(
            "goal",
            "nice",
            "funny" => array(
                'name' => 'ardi',
                'tel'   =>'07415517499',
                "vary",
                "fields" => array(
                    'small',
                    'email' => '[e-mail]'
                ),

                'good old days'

            ),

            "notes" => "come on lads lets enjoy this",
            "cast" => array(
                'Tom Cruise',
                'Thomas Muller' => array('age' => 24)
            )
        );

        // Expected xml value
        $expectedXmlEl = new SimpleXMLElement('<root/>'); 
        $expectedXmlEl->addChild('item0', $testArray[0]);
        $expectedXmlEl->addChild('item1', $testArray[1]);
        $childEl = $expectedXmlEl->addChild('funny');
        $childEl->addChild("name", $testArray['funny']['name']);
        $childEl->addChild("tel", $testArray['funny']['tel']);
        $childEl->addChild("item0", "vary");
        $childChildEl = $childEl->addChild("fields");
        $childChildEl->addChild('item0', 'small');
        $childChildEl->addChild('email', $testArray['funny']['fields']['email']);
        $childEl->addChild("item1", 'good old days');
        $expectedXmlEl->addChild('notes', $testArray['notes']);
        $childEl2 = $expectedXmlEl->addChild('cast');
        $childEl2->addChild('item0', 'Tom Cruise');
        $childChildEl2 = $childEl2->addChild('Thomas Muller');
        $childChildEl2->addChild('age', $testArray['cast']['Thomas Muller']['age']);

        // What the function produces       
        $actualXmlEl = new SimpleXMLElement('<root/>');
        arrayToXml($testArray, $actualXmlEl);

        $this->assertEquals($expectedXmlEl->asXML(), $actualXmlEl->asXML());
    }
}      

Answer 5

I would have commented the second most voted answer, because it doesn't preserve structure and generates bad xml if there is numerically indexed inner arrays.

I developed my own version based on it, because I needed simple converter between json and xml regardless of the structure of data. My version preserves numeric key information and structure of the original array. It creates elements for the numerically indexed values by wrapping values to value -named elements with key-attribute that contains numerical key.

For example

array('test' => array(0 => 'some value', 1 => 'other'))

converts to

<test><value key="0">some value</value><value key="1">other</value></test>

My version of array_to_xml -function (hope it helps somebody :)

function array_to_xml($arr, &$xml) {
    foreach($arr as $key => $value) {
        if(is_array($value)) {
            if(!is_numeric($key)){
                $subnode = $xml->addChild("$key");
            } else {
                $subnode = $xml->addChild("value");
                $subnode->addAttribute('key', $key);                    
            }
            array_to_xml($value, $subnode);
        }
        else {
            if (is_numeric($key)) {
                $xml->addChild("value", $value)->addAttribute('key', $key);
            } else {
                $xml->addChild("$key",$value);
            }
        }
    }
}   

Answer 6

<?php
function array_to_xml(array $arr, SimpleXMLElement $xml)
{
    foreach ($arr as $k => $v) {
        is_array($v)
            ? array_to_xml($v, $xml->addChild($k))
            : $xml->addChild($k, $v);
    }
    return $xml;
}

$test_array = array (
    'bla' => 'blub',
    'foo' => 'bar',
    'another_array' => array (
        'stack' => 'overflow',
    ),
);

echo array_to_xml($test_array, new SimpleXMLElement('<root/>'))->asXML();