How do you parse and process HTML/XML in PHP?
Parsing and processing HTML/XML in PHP enables the extraction of information from web pages and structured data. There are several approaches available, each with its own advantages and limitations.
Native XML Extensions:
- DOM (Document Object Model): A language-agnostic interface that allows access and manipulation of XML documents. It's versatile, capable of parsing broken HTML, and supports XPath queries.
- XMLReader: A pull parser that provides a sequential view of an XML document. It has a more compact approach compared to DOM.
- XML Parser: A push parser that triggers handlers for specific XML events. It offers fine-grained control but can be complex to work with.
- SimpleXML: A simplified interface for converting XML into an object that can be accessed using property selectors and array iterators. It's suitable for parsing well-formed HTML.
3rd Party Libraries (libxml-based):
- FluentDom: Provides a jQuery-like API for DOM manipulation, with support for XPath and CSS selectors, and additional features.
- HtmlPageDom: Extends Symfony's DomCrawler for HTML manipulation, offering simplified methods and shortcuts.
- phpQuery: A chainable CSS selector-driven DOM API, providing a jQuery-like interface.
- laminas-dom: A feature-complete library with a focus on XPath and CSS selector querying.
- fDOMDocument: Extends the DOM to leverage exceptions and adds custom methods for convenience.
- sabre/xml: Wraps XMLReader and XMLWriter to create an "xml to object/array" mapping system, enabling efficient parsing of large XML files.
- FluidXML: Facilitates XML manipulation through a chainable API, utilizing XPath and the fluent programming pattern.
3rd Party (not libxml-based):
- PHP Simple HTML DOM Parser: A lightweight library for parsing HTML, supporting CSS selectors and extraction of content.
- PHP Html Parser: A flexible parser based on CSS selectors, designed for scraping HTML, including broken HTML.
HTML 5:
- HTML5DomDocument: Extends DOMDocument to fix bugs and add features such as HTML entity preservation, void tag support, and CSS selector querying.
- HTML5: A standalone HTML5 parser and writer written in PHP, providing features like a DOM tree builder and support for PHP namespaces.
Regular Expressions:
Not recommended, regular expressions can be used for HTML extraction but are discouraged due to their brittleness and lack of understanding of HTML syntax. However, custom parsers using regular expressions can be reliable, but creating a complete and reliable parser is time-consuming.
The above is the detailed content of How to Parse and Process HTML/XML in PHP?. For more information, please follow other related articles on the PHP Chinese website!

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