XML Utils for php

gistfile1.php

class XmlUtils
{
    function removeChildren(&$node) 
    {
        while ($node->firstChild) 
        {
            while ($node->firstChild->firstChild) 
            {
                XmlUtils::removeChildren($node->firstChild);
            }
            $node->removeChild($node->firstChild);
        }
    }
    
    public static function insertNode($newNode, $refNode, $insertMode=null) 
    {
        if(!$insertMode || $insertMode == "inside") 
        {
           
            $refNode->appendChild($newNode);
           
        } 
        else if($insertMode == "before") 
        {
           
            $refNode->parentNode->insertBefore($newNode, $refNode);
           
        } 
        else if($insertMode == "after") 
        {
           
            if($refNode->nextSibling) {
                $refNode->parentNode->insertBefore($newNode, $refNode->nextSibling);
            } else {
                $refNode->parentNode->appendChild($newNode);
            }     
                 
        }
       
    }
    
    function addTagWithTabs(&$str, $value, $level=0) 
    {
        if (is_array($level))
            $level=count($level);
        
        $level=$level+1;
        
        //$str.=str_repeat(CHR(9),$level).$value.CHR(10);
        $str .= str_repeat ( "    ", $level ) . $value . CHR ( 10 );
    }

    public function printXml($xmlStr) 
    {
        print_r ( "<pre>" . htmlentities ( XmlUtils::formatXmlString($xmlStr) ) . "</pre>" );
    }

    public static function formatXmlString($xml)
    {
        $html_output=false;
        $xml_obj = new SimpleXMLElement($xml);
        $level = 4;
        $indent = 0; // current indentation level
        $pretty = array();

        // get an array containing each XML element
        $xml = explode("\n", preg_replace('/>\s*</', ">\n<", $xml_obj->asXML()));

        // shift off opening XML tag if present
        if (count($xml) && preg_match('/^<\?\s*xml/', $xml[0])) {
            $pretty[] = array_shift($xml);
        }

        foreach ($xml as $el) {
            if (preg_match('/^<([\w])+[^>\/]*>$/U', $el)) {
                // opening tag, increase indent
                $pretty[] = str_repeat(' ', $indent) . $el;
                $indent += $level;
            } else {
                if (preg_match('/^<\/.+>$/', $el)) {
                    $indent -= $level;  // closing tag, decrease indent
                }
                if ($indent < 0) {
                    $indent += $level;
                }
                $pretty[] = str_repeat(' ', $indent) . $el;
            }
        }
        $xml = implode("\n", $pretty);
        return ($html_output) ? htmlentities($xml) : $xml;
    }
    
    public static function getElementById(&$nodeRoot, &$xmlDoc, $id)
    {
        $value=$nodeRoot->getAttribute("id");
    
        if ($nodeRoot->hasAttribute("id") && (!strcmp($value,$id)))
        {
            return $nodeRoot;
        }
    
        if ($nodeRoot->hasChildNodes())
        {
            foreach($nodeRoot->childNodes as $child)
            {
                if (get_class($child)=='DOMElement')
                {
                    $node=XmlUtils::getElementById($child,$xmlDoc,$id);
                    if ($node!=NULL)
                        return $node;   
                }
            }
        }
        return NULL;
    }
}