On DevShed today, they continue their series looking at working with XML in PHP with the DOM functionality with the fifth part of their series, a look at working with HTML strings and file data.

Understanding how to use the methods and properties provided by this library requires a little effort from you, despite its fairly easy learning curve. [...] The DOM XML extension has plenty of options when it comes to moving portions of an XML document (or even the entire document) from one place to another. This is certainly a process that can be performed with minor hassles by utilizing the intuitive DOM API mentioned in the beginning.

They show how to use loadHTML to pull in the text from an HTML string and use loadHTMLFile to pull it in from an external HTML file. Finally, they show how to write the data and whatever changes you might have made to it, back out to a file with saveHTMLFile.