以上答案大部分是正确的。然而，我想出了这个答案，它解决了array_walk_recursive的兼容性问题，也解决了数值键的问题。它也通过了我做的所有测试:

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);
    }
}   

我还为此添加了一个测试类，你可能会发现有用:

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' => 'ardi.eshghi@gmail.com'
                ),

                '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());
    }
}      

其他解决方案:

$marray=array(....);
$options = array(
                "encoding" => "UTF-8",
                "output_type" => "xml", 
                "version" => "simple",
                "escaping" => array("non-ascii, on-print, markup")
                );
$xmlres = xmlrpc_encode_request('root', $marray, $options);
print($xmlres);

使用FluidXML，您可以从一个PHP数组开始，生成一个用于SimpleXML的XML…只有两行代码。

$fluidxml  = fluidxml($array);
$simplexml = simplexml_import_dom($fluidxml->dom());

一个示例数组可以是

$array = [ 'doc' => [
              'fruit' => 'orange',
              'cake'  => [
                   '@id' => '123', 
                   '@'   => 'tiramisu' ],
              [ 'pasta' => 'matriciana' ],
              [ 'pasta' => 'boscaiola'  ]
] ];

https://github.com/servo-php/fluidxml

这是我的入口，简单而干净。

function array2xml($array, $xml = false){
    if($xml === false){
        $xml = new SimpleXMLElement('<root/>');
    }
    foreach($array as $key => $value){
        if(is_array($value)){
            array2xml($value, $xml->addChild($key));
        }else{
            $xml->addChild($key, $value);
        }
    }
    return $xml->asXML();
}


header('Content-type: text/xml');
print array2xml($array);

你可以使用胡子模板引擎，并制作一个模板，如:

{{#RECEIVER}}
<RECEIVER>
    <COMPANY>{{{COMPANY}}}</COMPANY>
    <CONTACT>{{{CONTACT}}}</CONTACT>
    <ADDRESS>{{{ADDRESS}}}</ADDRESS>
    <ZIP>{{ZIP}}</ZIP>
    <CITY>{{{CITY}}}</CITY>
</RECEIVER>
{{/RECEIVER}}
{{#DOC}}
<DOC>
    <TEXT>{{{TEXT}}}</TEXT>
    <NUMBER>{{{NUMBER}}}</NUMBER>
</DOC>
{{/DOC}}

在PHP中这样使用它:

require_once( __DIR__ .'/../controls/Mustache/Autoloader.php' );
Mustache_Autoloader::register();
$oMustache = new Mustache_Engine();
$sTemplate = implode( '', file( __DIR__ ."/xml.tpl" ));
$return = $oMustache->render($sTemplate, $res);
echo($return);

整个XML结构定义在$data数组中:

function array2Xml($data, $xml = null)
{
    if (is_null($xml)) {
        $xml = simplexml_load_string('<' . key($data) . '/>');
        $data = current($data);
        $return = true;
    }
    if (is_array($data)) {
        foreach ($data as $name => $value) {
            array2Xml($value, is_numeric($name) ? $xml : $xml->addChild($name));
        }
    } else {
        $xml->{0} = $data;
    }
    if (!empty($return)) {
        return $xml->asXML();
    }
}