HTML Agility to extract PHP tags

What syntax should be used with HTML Agility Pack to extract all

Tags from a Php file..?

HtmlNodeCollection tags = htmlDoc.DocumentNode.SelectNodes("//??php");

Throws an exception (开发者_Go百科invalid token).

Tried escaping ? with ?? and \?

Thanks

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HTML Agility Pack does choke on nodes with ? in the name. The simplest option is probably to go through the HTML string before you load it into a document object and replace instances of <? with <php and so-on. That doesn't handle any nasty cases like having a string literal on the page with "&lt?" but really, how often does that happen?