Cookbooks
PHP
Chapter 11. HTML and the Web
Parsing HTML

PHP:
Parsing HTML

How to:

For parsing HTML, PHP programmers can utilize built-in functions or lean on robust libraries like Simple HTML DOM Parser. Here, we’ll explore examples using both PHP’s DOMDocument and the Simple HTML DOM Parser.

Using DOMDocument:

PHP’s DOMDocument class is a part of its DOM extension, allowing for parsing and manipulating HTML and XML documents. Here’s a quick example on how to use DOMDocument to find all the images in an HTML document:

$html = <<<HTML
<!DOCTYPE html>
<html>
<head>
    <title>Sample Page</title>
</head>
<body>
    <img src="image1.jpg" alt="Image 1">
    <img src="image2.jpg" alt="Image 2">
</body>
</html>
HTML;

$doc = new DOMDocument();
@$doc->loadHTML($html);
$images = $doc->getElementsByTagName('img');

foreach ($images as $img) {
    echo $img->getAttribute('src') . "\n";
}

Sample output:

image1.jpg
image2.jpg

Using Simple HTML DOM Parser:

For more complex tasks or easier syntax, you might prefer using a third-party library. Simple HTML DOM Parser is a popular choice, providing a jQuery-like interface for navigating and manipulating HTML structures. Here’s how to use it:

First, install the library using Composer:

composer require simple-html-dom/simple-html-dom

Then, manipulate HTML to, for example, find all links:

require_once 'vendor/autoload.php';

use simplehtmldom\HtmlWeb;

$client = new HtmlWeb();
$html = $client->load('http://www.example.com');

foreach($html->find('a') as $element) {
    echo $element->href . "\n";
}

This code snippet will fetch the HTML content of ‘http://www.example.com’, parse it, and print out all the hyperlinks. Remember to replace 'http://www.example.com' with the actual URL you wish to parse.

Utilizing these methods, PHP developers can effectively parse HTML content, tailor data extraction to their needs, or seamlessly integrate external web content into their projects.

Downloading a web pageSending an HTTP request