php xml 转array 函数 （原创）

/**                                                                                                                                                           
     *Author zhudongchang                                                                                                                                         
     *Date 2015/6/12    原创                                                                                                                                        
     *xml 转array 函数                                                                                                                                 
     *@param string $xmlStr xml字符串                                                                                                                   
     *@return string 
     */
    public static function convertXmlToArray($xmlStr){
        $patten=<<<EOT
/(^s*<(s*[a-zA-Z0-9_='":]+s*)+>.*<s*/(s*[a-zA-Z0-9_='":]+s*)+>s*$)|(^s*<(s*[a-zA-Z0-9_='":]+s*)+/s*>$)/s
EOT;
        $pattenChildXml=<<<EOT
/^s*<(s*[a-zA-Z0-9_='":]+s*)+>(.*)<s*/(s*[a-zA-Z0-9_='":]+s*)+>s*$/s
EOT;
        $res=array();
        $xml = simplexml_load_string($xmlStr);
        foreach($xml->children() as $val){
            $key=$val->getName();            
            $valXml=$val->asXML();        
            preg_match($pattenChildXml,$valXml,$match);
            $childXmlStr=$match[2];
            //var_dump($match,$valXml,$childXmlStr);die();
            $temp=preg_match($patten,$childXmlStr)?self::convertXmlToArray($valXml):(string)$val;
            if(array_key_exists($key,$res)){
                is_array($res[$key]) or $res[$key]=array($res[$key]);                
                $tempNew=array();
                foreach($res[$key] as $k =>$v){
                    if(!is_int($k)){
                        $tempNew[]=$v;
                        unset($res[$key][$k]);
                    }
                }                
                empty($tempNew) or $res[$key][]=$tempNew;
                $res[$key][]=$temp;
            }else{
                $res[$key]=$temp;
            }
        }
        return $res;
    }