Extend style attribute in DOM element php

Question

I want to clean up the content of many text columns in the database which contain HTML code, generated by different wysiwyg editors.

In this case, I want to remove the align attributes and append it to the style attribute style='text-align: left|right|center' in every paragraphs. I also want to be sure I don't delete the existing values of the style attribute. I decided for this reason I will use the DOMDocument. I didn't find a way to simple append a new value to an existing attribute.

Let me know if there is a better or more performance wise way of doing it, without 3rd party library (like SQL queries or REGEXP).

$DOMDoc = new DOMDocument('1.0', 'UTF-8');
$DOMDoc->loadHTML(mb_convert_encoding($text, 'HTML-ENTITIES', 'UTF-8'), LIBXML_HTML_NODEFDTD | LIBXML_COMPACT | LIBXML_NOERROR | LIBXML_NOWARNING);

/** @var DOMElement $paragraph */
foreach($DOMDoc->getElementsByTagName('p') as $paragraph) {
    moveAttributeToStyle($paragraph, 'align', 'text-align');
}

/**
 * @param DOMElement $paragraph
 * @param string $htmlAttrName
 * @param string $cssAttrName
 */
function moveAttributeToStyle(&$paragraph, $htmlAttrName, $cssAttrName)
{
    if ($paragraph->hasAttribute($htmlAttrName)) {
        $htmlAttrValue = $paragraph->getAttribute($htmlAttrName);
        $paragraph->removeAttribute($htmlAttrName);

        if ($paragraph->hasAttribute('style')) {
            $attributes = explode(';', $paragraph->getAttribute('style'));
            $attributes[] = sprintf('%s: %s;', $cssAttrName, $htmlAttrValue);
            $paragraph->setAttribute('style', implode('; ', array_filter(array_map('trim', $attributes))));
        } else {
            $paragraph->setAttribute('style', sprintf('%s: %s;', $cssAttrName, $htmlAttrValue));
        }
    }
}

$text = preg_replace('~<(?:!DOCTYPE|/?(?:html|head|body))[^>]*>\s*~i', '', $DOMDoc->saveHTML());

“I didn't find a way to simple append a new value to an existing attribute.” - read existing value into variable, append new text to that, and then set the attribute (again) using that variable …? — CBroe
@CBroe: this is what my logic does above. What I miss here is something like this: $paragraph->getAttribute('style')->append('text-align', 'left'); — Zoltán Süle
That doesn’t exist in any DOM implementation I am aware of. And I’d say it is just too rare a use case to justify the existence of such a method. — CBroe

Flash Thunder Flash Thunder · Accepted Answer · 2018-01-08T16:21:41

I would suggest to use PHP Simple HTML DOM Parser

Example code:

// Create DOM from string
$html = str_get_html('<div id="hello">Hello</div><div id="world">World</div>');

$html->find('div', 1)->class = 'bar';

$html->find('div[id=hello]', 0)->innertext = 'foo';

echo $html; // Output: <div id="hello">foo</div><div id="world" class="bar">World</div>

Please visit the given link for more information.

Extend style attribute in DOM element php

1 Answers