PHP XML Parsing

Question

Which is the best way to parse an XML file in PHP ?

First
Using the DOM object

//code
$dom = new DOMDocument();
$dom->load(         


        

Answer 1

I have started to use XMLReader to parse the XML files. After doing a bit of googling around found it the best to way parse XML files as it does not load the whole XML file into memory. Say if suppose my XML files was of 5 MB, while parsing it using XMLReader 5MB of my memory does not get wasted.

//usage
$xml = new XMLReader();
$xml->XML($xmlString);
while($xml->read)
{
if($xml->localName == 'Something') // check if tag name equals something
{
//do something
}
}

Using XML Reader we can find if the current tag is an opening tag or closing tag and do the needful as required.

Answer 2

It depends on the document you're passing, but XMLReader is usually the faster than both simplexml and DOM (http://blog.liip.ch/archive/2004/05/10/processing_large_xml_documents_with_php.html). Personally though I've never used XMLReader and usually decided which to use depending on whether or not I need to edit it:

• simplexml if I'm just reading a document
• DOM if I'm modifying the DOM and saving it back

You can also convert objects between simplexml and DOM.

Answer 3

If you're processing huge files don't parse them. Apply XSLT instead. That'll save you huge amounts of memory and processing time.

Answer 4

All XML is handled by simpleXML in PHP now when I develop. It's easily extended and methods overwritten when needed.

Answer 5

I prefer simplexml_load_string for ease of use. Processing speed may well depend on the format of the XML file if the two use different methods of parsing the file - try it out on your own files and see which is better for you.