这里有一个函数帮我解决了这个问题:

就像这样叫它

echo arrayToXml("response",$arrayIWantToConvert);
function arrayToXml($thisNodeName,$input){
        if(is_numeric($thisNodeName))
            throw new Exception("cannot parse into xml. remainder :".print_r($input,true));
        if(!(is_array($input) || is_object($input))){
            return "<$thisNodeName>$input</$thisNodeName>";
        }
        else{
            $newNode="<$thisNodeName>";
            foreach($input as $key=>$value){
                if(is_numeric($key))
                    $key=substr($thisNodeName,0,strlen($thisNodeName)-1);
                $newNode.=arrayToXml3($key,$value);
            }
            $newNode.="</$thisNodeName>";
            return $newNode;
        }
    }

一个简短的例子:

<?php

$test_array = array (
  'bla' => 'blub',
  'foo' => 'bar',
  'another_array' => array (
    'stack' => 'overflow',
  ),
);
$xml = new SimpleXMLElement('<root/>');
array_walk_recursive($test_array, array ($xml, 'addChild'));
print $xml->asXML();

结果

<?xml version="1.0"?>
<root>
  <blub>bla</blub>
  <bar>foo</bar>
  <overflow>stack</overflow>
</root>

键和值会被交换——你可以在array_walk之前用array_flip()来修复这个问题。array_walk_recursive需要PHP 5。你可以用array_walk代替，但你不会得到'stack' => 'overflow'在XML中。

基于这里的所有其他内容，通过前缀@处理数值索引+属性，并可以将xml注入到现有节点:

Code

function simple_xmlify($arr, SimpleXMLElement $root = null, $el = 'x') {
    // based on, among others http://stackoverflow.com/a/1397164/1037948

    if(!isset($root) || null == $root) $root = new SimpleXMLElement('<' . $el . '/>');

    if(is_array($arr)) {
        foreach($arr as $k => $v) {
            // special: attributes
            if(is_string($k) && $k[0] == '@') $root->addAttribute(substr($k, 1),$v);
            // normal: append
            else simple_xmlify($v, $root->addChild(
                    // fix 'invalid xml name' by prefixing numeric keys
                    is_numeric($k) ? 'n' . $k : $k)
                );
        }
    } else {
        $root[0] = $arr;
    }

    return $root;
}//--   fn  simple_xmlify

使用

// lazy declaration via "queryparam"
$args = 'hello=4&var[]=first&var[]=second&foo=1234&var[5]=fifth&var[sub][]=sub1&var[sub][]=sub2&var[sub][]=sub3&var[@name]=the-name&var[@attr2]=something-else&var[sub][@x]=4.356&var[sub][@y]=-9.2252';
$q = array();
parse_str($val, $q);

$xml = simple_xmlify($q); // dump $xml, or...
$result = get_formatted_xml($xml); // see below

结果

<?xml version="1.0"?>
<x>
  <hello>4</hello>
  <var name="the-name" attr2="something-else">
    <n0>first</n0>
    <n1>second</n1>
    <n5>fifth</n5>
    <sub x="4.356" y="-9.2252">
      <n0>sub1</n0>
      <n1>sub2</n1>
      <n2>sub3</n2>
    </sub>
  </var>
  <foo>1234</foo>
</x>

好处:格式化XML

function get_formatted_xml(SimpleXMLElement $xml, $domver = null, $preserveWhitespace = true, $formatOutput = true) {
    // http://stackoverflow.com/questions/1191167/format-output-of-simplexml-asxml

    // create new wrapper, so we can get formatting options
    $dom = new DOMDocument($domver);
    $dom->preserveWhiteSpace = $preserveWhitespace;
    $dom->formatOutput = $formatOutput;
    // now import the xml (converted to dom format)
    /*
    $ix = dom_import_simplexml($xml);
    $ix = $dom->importNode($ix, true);
    $dom->appendChild($ix);
    */
    $dom->loadXML($xml->asXML());

    // print
    return $dom->saveXML();
}//--   fn  get_formatted_xml

只是对上面的函数进行了编辑，当键是数字时，添加前缀“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");
               }
          }
     }
}

总之……我使用了onokazu的代码(谢谢!)，并添加了在XML中重复标记的能力，它还支持属性，希望有人发现它有用!

 <?php

function array_to_xml(array $arr, SimpleXMLElement $xml) {
        foreach ($arr as $k => $v) {

            $attrArr = array();
            $kArray = explode(' ',$k);
            $tag = array_shift($kArray);

            if (count($kArray) > 0) {
                foreach($kArray as $attrValue) {
                    $attrArr[] = explode('=',$attrValue);                   
                }
            }

            if (is_array($v)) {
                if (is_numeric($k)) {
                    array_to_xml($v, $xml);
                } else {
                    $child = $xml->addChild($tag);
                    if (isset($attrArr)) {
                        foreach($attrArr as $attrArrV) {
                            $child->addAttribute($attrArrV[0],$attrArrV[1]);
                        }
                    }                   
                    array_to_xml($v, $child);
                }
            } else {
                $child = $xml->addChild($tag, $v);
                if (isset($attrArr)) {
                    foreach($attrArr as $attrArrV) {
                        $child->addAttribute($attrArrV[0],$attrArrV[1]);
                    }
                }
            }               
        }

        return $xml;
    }

        $test_array = array (
          'bla' => 'blub',
          'foo' => 'bar',
          'another_array' => array (
            array('stack' => 'overflow'),
            array('stack' => 'overflow'),
            array('stack' => 'overflow'),
          ),
          'foo attribute1=value1 attribute2=value2' => 'bar',
        );  

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

        echo "$xml\n";
        $dom = new DOMDocument;
        $dom->preserveWhiteSpace = FALSE;
        $dom->loadXML($xml);
        $dom->formatOutput = TRUE;
        echo $dom->saveXml();
    ?>

另一个改进:

/**
* Converts an array to XML
*
* @param array $array
* @param SimpleXMLElement $xml
* @param string $child_name
*
* @return SimpleXMLElement $xml
*/
public function arrayToXML($array, SimpleXMLElement $xml, $child_name)
{
    foreach ($array as $k => $v) {
        if(is_array($v)) {
            (is_int($k)) ? $this->arrayToXML($v, $xml->addChild($child_name), $v) : $this->arrayToXML($v, $xml->addChild(strtolower($k)), $child_name);
        } else {
            (is_int($k)) ? $xml->addChild($child_name, $v) : $xml->addChild(strtolower($k), $v);
        }
    }

    return $xml->asXML();
}

用法:

$this->arrayToXML($array, new SimpleXMLElement('<root/>'), 'child_name_to_replace_numeric_integers');