Parsing HTML to return CSS rules from ids and classes attributes with PHP

I hate to have to write down a lot of CSS rules and then enter my styles in it, so I'd like to develop a tiny php script that would parse the HTML I'd pass to it and then return empty CSS rules.

I decided to use PHP's DomDocument.

The question is: How could I loop through the whole structure? (I saw that for example DomDocument only has getElementByTag or getElementById and no getFirstElement for example)

I only want to get the ids and the 开发者_运维问答classes in a given block of HTML code, I'd pass things like:

<div id="testId">
    <div class="testClass">
        <span class="message error">hello world</span>
    </div>
</div>

I only want to know how could I loop through every node?

Thanks!

You can pass an asterisk (*) to getElementsByTagName to get all tags and then loop through them...

<?php

 $nodes = $xml->getElementsByTagName("*");
 $css = "";

 for ($i = 0; $i < $nodes->length; $i ++)
 {
    $node = $nodes->item($i);    
    if ($node->hasAttribute("class")) {
      $css = $css . "." . $node->getAttribute("class") . " { }\n";
    } elseif ($node->hasAttribute("id")) {
      $css = $css . "#" . $node->getAttribute("id") . " { }\n";
    }
 }

 echo $css;

?>

The SimpleXML extension for PHP may help you. It work perfectly to navigate through HTML tree.

http://www.php.net/manual/en/simplexml.examples-basic.php