我的答案，拼凑别人的答案。这应该可以纠正无法补偿数字键的错误:

function array_to_xml($array, $root, $element) {
    $xml = new SimpleXMLElement("<{$root}/>");
    foreach ($array as $value) {
        $elem = $xml->addChild($element);
        xml_recurse_child($elem, $value);
    }
    return $xml;
}

function xml_recurse_child(&$node, $child) {
    foreach ($child as $key=>$value) {
        if(is_array($value)) {
            foreach ($value as $k => $v) {
                if(is_numeric($k)){
                    xml_recurse_child($node, array($key => $v));
                }
                else {
                    $subnode = $node->addChild($key);
                    xml_recurse_child($subnode, $value);
                }
            }
        }
        else {
            $node->addChild($key, $value);
        }
    }   
}

array_to_xml()函数假定数组首先由数字键组成。如果数组有一个初始元素，则可以从array_to_xml()函数中删除foreach()和$elem语句，只传递$xml。

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());
    }
}      

如果数组是关联的并且键是正确的，那么首先将它转换为xml可能会更容易。喜欢的东西:

  function array2xml ($array_item) {
    $xml = '';
    foreach($array_item as $element => $value)
    {
        if (is_array($value))
        {
            $xml .= "<$element>".array2xml($value)."</$element>";
        }
        elseif($value == '')
        {
            $xml .= "<$element />";
        }
        else
        {
            $xml .= "<$element>".htmlentities($value)."</$element>";
        }
    }
    return $xml;
}

$simple_xml = simplexml_load_string(array2xml($assoc_array));

另一种方法是首先创建基本的xml，例如

$simple_xml = simplexml_load_string("<array></array>");

然后对于数组的每个部分，使用类似于我的文本创建循环的东西，而不是使用simplexml函数“addChild”用于数组的每个节点。

稍后我将尝试使用这两个版本来更新这篇文章。

下面讨论名称空间。在本例中，构造包装器以包含名称空间定义，并将其传递给函数。使用冒号来标识命名空间。

测试数组

$inarray = [];
$inarray['p:apple'] = "red";
$inarray['p:pear'] = "green";
$inarray['p:peach'] = "orange";
$inarray['p1:grocers'] = ['p1:local' => "cheap", 'p1:imported' => "expensive"];


$xml = new SimpleXMLElement( '<p:wrapper xmlns:p="http://namespace.org/api" xmlns:p1="http://namespace.org/api2 /> ');

array_to_xml($xml,$inarray); 




function array_to_xml(SimpleXMLElement $object, array $data)
{   
    $nslist = $object->getDocNamespaces();

    foreach ($data as $key => $value)
    {   
        $nspace = null;
        $keyparts = explode(":",$key,2);
        if ( count($keyparts)==2) 
            $nspace = $nslist[$keyparts[0]];

        if (is_array($value))
        {   
            $key = is_numeric($key) ? "item$key" : $key;
            $new_object = $object->addChild($key,null,$nspace);
            array_to_xml($new_object, $value);
        }   
        else
        {   
            $key = is_numeric($key) ? "item$key" : $key;
            $object->addChild($key, $value,$nspace);
        }   
    }   
}   

这里提供的答案仅将数组转换为带节点的XML，不能设置属性。我已经编写了一个php函数，允许您将数组转换为php，并为xml中的特定节点设置属性。这里的缺点是您必须以很少约定的特定方式构造数组(仅当您想使用属性时)

下面的示例也允许您用XML设置属性。

来源可以在这里找到: https://github.com/digitickets/lalit/blob/master/src/Array2XML.php

<?php    
$books = array(
    '@attributes' => array(
        'type' => 'fiction'
    ),
    'book' => array(
        array(
            '@attributes' => array(
                'author' => 'George Orwell'
            ),
            'title' => '1984'
        ),
        array(
            '@attributes' => array(
                'author' => 'Isaac Asimov'
            ),
            'title' => 'Foundation',
            'price' => '$15.61'
        ),
        array(
            '@attributes' => array(
                'author' => 'Robert A Heinlein'
            ),
            'title' => 'Stranger in a Strange Land',
            'price' => array(
                '@attributes' => array(
                    'discount' => '10%'
                ),
                '@value' => '$18.00'
            )
        )
    )
);
/* creates 
<books type="fiction">
  <book author="George Orwell">
    <title>1984</title>
  </book>
  <book author="Isaac Asimov">
    <title>Foundation</title>
    <price>$15.61</price>
  </book>
  <book author="Robert A Heinlein">
    <title>Stranger in a Strange Land</title>
    <price discount="10%">$18.00</price>
  </book>
</books>
*/
?>

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;
        }
    }