$re = '~<div\ class="myclass">
[\s\S]*?
</div>
(*SKIP)(*FAIL)
|
<a[^>]*>.*?</a>~x';
$str = '<p>Hi Hello <a href="#">World</a></p>.
This is <div class="myclass">testing <a href="#">content</a>.
some more content</div>. One more <a href="#"> Link </a>.';
$subst = "";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php