来自PHP 5.4

function array2xml($data, $root = null){
    $xml = new SimpleXMLElement($root ? '<' . $root . '/>' : '<root/>');
    array_walk_recursive($data, function($value, $key)use($xml){
        $xml->addChild($key, $value);
    });
    return $xml->asXML();
}

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。

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。

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();
    }
}

来自PHP 5.4

function array2xml($data, $root = null){
    $xml = new SimpleXMLElement($root ? '<' . $root . '/>' : '<root/>');
    array_walk_recursive($data, function($value, $key)use($xml){
        $xml->addChild($key, $value);
    });
    return $xml->asXML();
}

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());
    }
}