php array cover to xml

参考

http://stackoverflow.com/questions/1397036/how-to-convert-array-to-simplexml

<?php
class FileTools {
	/**
	 * 内部函数
	 *
	 * @param array $arr        	
	 * @param SimpleXMLElement $xml        	
	 * @return SimpleXMLElement
	 */
	static 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 )) {
					self::_array_to_xml ( $v, $xml );
				} else {
					$child = $xml->addChild ( $tag );
					if (isset ( $attrArr )) {
						foreach ( $attrArr as $attrArrV ) {
							$child->addAttribute ( $attrArrV [0], $attrArrV [1] );
						}
					}
					self::_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;
	}
	/**
	 *
	 * @param array $array
	 *        	需要转化的数组
	 * @param string $root
	 *        	根标签
	 * @param boolean $formatoutput
	 *        	是否需要格式化输出
	 * @param boolean $preserveWhiteSpace
	 *        	是否过滤标签之间的空白
	 * @throws Exception
	 * @return mixed Ambigous mixed>
	 */
	static function array_to_xml($array = array(), $root, $formatoutput = false, $preserveWhiteSpace = false) {
		if (empty ( $root )) {
			throw new Exception ( '根标签不能为空' );
		}
		if (! preg_match ( '/^<w+/?>$/', $root )) {
			throw new Exception ( '标签格式异常' );
		}
		$xml = self::_array_to_xml ( $array, new SimpleXMLElement ( $root ) )->asXML ();
		if ($formatoutput || $preserveWhiteSpace) {
			if (! class_exists ( "DOMDocument" ))
				return $xml;
			$dom = new DOMDocument ();
			$dom->preserveWhiteSpace = $preserveWhiteSpace;
			$dom->loadXML ( $xml );
			$dom->formatOutput = $formatoutput;
			$xml = $dom->saveXml ();
		}
		return $xml;
	}
}