Ever need to constuct XML on the fly? Like maybe with XML APIs… Are all your inputs/values are as asociative arrays?

Finding myself in that boat pretty often, I have created this simple library to convert associative arrays into XML.

You can do this two ways:

ArrayToXml::build($array)

• uses CakePHP’s XmlHelper to construct,
• this lets you construct XML segments easier, which you can put together later
• NOTE: this XML will not have a root element, unless the array does

or if you prefer SimpleXml (which is faster)

ArrayToXml::simplexml($array, $rootNodeName, $rootNodeAttributes)

• NOTE: this assumes the $array doesn’t have a root element

The $array should be structured as you want the XML structured, keys as elements.

$array = array(
  'Parent' => array(
		'Child1' => array('id' => 1234, 'name' => 'child 1'),
		'Child2' => array('id' => 9876, 'name' => 'child 2'),
	),
);
$xmlStrBuild = str_replace("\n", "", ArrayToXml::build($array));
$expected = '<Parent><Child1><id>1234</id><name>child 1</name></Child1><Child2><id>9876</id><name>child 2</name></Child2></Parent>';
$this->assertEqual($xmlStrBuild, $expected);
$xmlStrBuild = str_replace("\n", "", ArrayToXml::build($array, true));
$expected = '<?xml version="1.0" encoding="UTF-8" ?><Parent><Child1><id>1234</id><name>child 1</name></Child1><Child2><id>9876</id><name>child 2</name></Child2></Parent>';
$this->assertEqual($xmlStrBuild, $expected);

$xmlStrSimple = str_replace("\n", "", ArrayToXml::simplexml($array['Parent'], 'Parent'));
$expected = '<?xml version="1.0"?><Parent><Child1><id>1234</id><name>child 1</name></Child1><Child2><id>9876</id><name>child 2</name></Child2></Parent>';
$this->assertEqual($xmlStrBuild, $expected);
$xmlStrSimple = str_replace("\n", "", ArrayToXml::simplexml($array, 'Root'));
$expected = '<?xml version="1.0"?><Root><Parent><Child1><id>1234</id><name>child 1</name></Child1><Child2><id>9876</id><name>child 2</name></Child2></Parent></Root>';
$this->assertEqual($xmlStrBuild, $expected);

If you want to inject attributes for any element, you can do so in one of two ways:

$array = array(
'Parent' => array(
	'attrib' => array('attr1' => 0),
	'Child1' => array('id' => 1234, 'name' => 'child 1', 'attrib' => array('attr1' => 1)),
	'Child2' => array('id' => 9876, 'name' => 'child 2', 'attrib' => array('attr1' => 2)),
	),
);
$xml = str_replace("\n", "", ArrayToXml::build($array));
$expected = '<Parent attr1="0"><Child1 attr1="1"><id>1234</id><name>child 1</name></Child1><Child2 attr1="2"><id>9876</id><name>child 2</name></Child2></Parent>';
$this->assertEqual($xml, $expected);

Or you can suffix the keys, separated by a pipe: (I like this method most of the time)

$array = array(
	'Parent|{"attr1":"0"}' => array(
		'Child1|{"attr1":"1"}' => array('id' => 1234, 'name' => 'child 1'),
		'Child2|{"attr1":"2"}' => array('id' => 9876, 'name' => 'child 2'),
	),
);
$xml = str_replace("\n", "", ArrayToXml::build($array));
$expected = '<Parent attr1="0"><Child1 attr1="1"><id>1234</id><name>child 1</name></Child1><Child2 attr1="2"><id>9876</id><name>child 2</name></Child2></Parent>';
$this->assertEqual($xml, $expected);

You can use this same trick to iterate over multiple nodes which should have the same name

$array = array(
	'Parent' => array(
		'Child|1' => array('id' => 1234, 'name' => 'child 1'),
		'Child|2' => array('id' => 9876, 'name' => 'child 2'),
		'Child|{"attr1":"with attributes"}|3' => array('id' => 3, 'name' => 'child 3'),
	),
);
$xml = str_replace("\n", "", ArrayToXml::build($array));
$expected = '<Parent><Child><id>1234</id><name>child 1</name></Child><Child><id>9876</id><name>child 2</name></Child><Child attr1="with attributes"><id>3</id><name>child 3</name></Child></Parent>';
$this->assertEqual($xml, $expected);

You can also use this helper function for this:

$array = array(
	'Parent' => array(
		array('id' => 1234, 'name' => 'child 1'),
		array('id' => 9876, 'name' => 'child 2', 'attrib' => array('attr1' => 2)),
	),
);
$array = ArrayToXml::add_tags($array, 'Child', true);
print_r($array); >>>
Array
(
	[Parent] => Array
		(
			[Child|0] => Array
				(
					[id] => 1234
					[name] => child 1
				)

			[Child|1] => Array
				(
					[id] => 9876
					[name] => child 2
					[attrib] => Array
						(
							[attr1] => 2
						)

				)

		)

)