多维PHP数组怎么转换成xml格式的数据

 $ar=array<br />( <br />	"auth"=> array <br />	(<br />		"user"=>  "customer" ,<br />		"password"=>  "password" ,<br />		"context"=>  "4" <br />	) ,<br />	"owner"=> array <br />	( <br />		"user"=>  "customer2" ,<br />		"context"=>  "4" <br />	) ,<br />	"language"=>  "en" ,<br />	"task"=> array<br />	( <br />		"code"=>  "0130" <br />	) <br />);<br /><br /><br />$doc = new DOMDocument('1.0','UTF-8');<br />// we want a nice output<br />$doc->formatOutput = true;<br /><br />$root = $doc->createElement('request');<br />$root = $doc->appendChild($root);<br /><br /> foreach($ar as $title=>$title_v){<br />   $title = $doc->createElement($title);<br />   $title = $root->appendChild($title); <br />    if(is_array($title_v)){<br />       foreach($title_v as $k=>$v){<br />	       $k = $doc->createElement($k);<br />           $k = $title->appendChild($k);<br />		   $text = $doc->createTextNode($v);<br />           $text = $k->appendChild($text);<br />	   } <br />   }else{<br />       $text = $doc->createTextNode($title_v);<br />       $text = $title->appendChild($text);<br />   }<br />}<br /><br />echo $doc->saveXML();

$ar = array( <br />	"auth" => array( <br />		"user" => "customer",<br />		"password" => "password",<br />		"context" => "4",<br />	),<br />	"owner" => array( <br />		"user" => "customer2",<br />		"context" => "4",<br />	),<br />	"language" => "en",<br />	"task" => array( <br />		"code" => "0130",<br />	), <br />);<br />$xml = simplexml_load_string('<request />');<br />create($ar, $xml);<br />echo $xml->saveXML();<br /><br />function create($ar, $xml) {<br />	foreach($ar as $k=>$v) {<br />		if(is_array($v)) {<br />			$x = $xml->addChild($k);<br />			create($v, $x);<br />		}else $xml->addChild($k, $v);<br />	}<br />}

<?xml version="1.0" ?> <br /><request><br />	<auth><br />		<user>customer</user> <br />		<password>password</password> <br />		<context>4</context> <br />	</auth><br />	<owner><br />		<user>customer2</user> <br />		<context>4</context> <br />	</owner><br />	<language>en</language> <br />	<task><br />		<code>0130</code> <br />	</task><br /></request>