PHP Simple HTML DOM Parser: Manual

# PHP Simple HTML DOM Parser Manual

## Index

- Quick Start
- How to create HTML DOM object?
- How to find HTML elements?
- How to access the HTML element's attributes?
- How to traverse the DOM tree?
- How to dump contents of DOM object?
- How to customize the parsing behavior?
- API Reference
- FAQ

## Quick Start

Top

- Get HTML elements
- Modify HTML elements
- Extract contents from HTML
- Scraping Slashdot!

// Create DOM from URL or file
$html = file_get_html('http://www.google.com/');
// Find all images
foreach($html->find('img') as $element)
echo $element->src . '<br>';
// Find all links
foreach($html->find('a') as $element)
echo $element->href . '<br>';
// Create DOM from string
$html = str_get_html('<div id="hello">Hello</div><div id="world">World</div>');
$html->find('div', 1)->class = 'bar';
$html->find('div[id=hello]', 0)->innertext = 'foo';
echo $html; // Output: <div id="hello">foo</div><div id="world" class="bar">World</div>
// Dump contents (without tags) from HTML
echo file_get_html('http://www.google.com/')->plaintext;
// Create DOM from URL
$html = file_get_html('http://slashdot.org/');
// Find all article blocks
foreach($html->find('div.article') as $article) {
$item['title'] = $article->find('div.title', 0)->plaintext;
$item['intro'] = $article->find('div.intro', 0)->plaintext;
$item['details'] = $article->find('div.details', 0)->plaintext;
$articles[] = $item;
}
print_r($articles);

## How to create HTML DOM object?

Top

- Quick way
- Object-oriented way

// Create a DOM object from a string
$html = str_get_html('<html><body>Hello!</body></html>');
// Create a DOM object from a URL
$html = file_get_html('http://www.google.com/');
// Create a DOM object from a HTML file
$html = file_get_html('test.htm');
// Create a DOM object
$html = new simple_html_dom();
// Load HTML from a string
$html->load('<html><body>Hello!</body></html>');
// Load HTML from a URL
$html->load_file('http://www.google.com/');
// Load HTML from a HTML file
$html->load_file('test.htm');

## How to find HTML elements?

Top

- Basics
- Advanced
- Descendant selectors
- Nested selectors
- Attribute Filters
- Text & Comments

// Find all anchors, returns a array of element objects
$ret = $html->find('a');
// Find (N)th anchor, returns element object or null if not found (zero based)
$ret = $html->find('a', 0);
// Find lastest anchor, returns element object or null if not found (zero based)
$ret = $html->find('a', -1);
// Find all <div> with the id attribute
$ret = $html->find('div[id]');
// Find all <div> which attribute id=foo
$ret = $html->find('div[id=foo]');
// Find all element which id=foo
$ret = $html->find('#foo');
// Find all element which class=foo
$ret = $html->find('.foo');
// Find all element has attribute id
$ret = $html->find('*[id]');
// Find all anchors and images
$ret = $html->find('a, img');
// Find all anchors and images with the "title" attribute
$ret = $html->find('a[title], img[title]');
Supports these operators in attribute selectors:

Filter | Description
--- | ---
[attribute] | Matches elements that have the specified attribute.
[!attribute] | Matches elements that don't have the specified attribute.
[attribute=value] | Matches elements that have the specified attribute with a certain value.
[attribute!=value] | Matches elements that don't have the specified attribute with a certain value.
[attribute^=value] | Matches elements that have the specified attribute and it starts with a certain value.
[attribute$=value] | Matches elements that have the specified attribute and it ends with a certain value.
[attribute*=value] | Matches elements that have the specified attribute and it contains a certain value.

// Find all <li> in <ul>
$es = $html->find('ul li');
// Find Nested <div> tags
$es = $html->find('div div div');
// Find all <td> in <table> which class=hello
$es = $html->find('table.hello td');
// Find all td tags with attribite align=center in table tags
$es = $html->find(''table td[align=center]');
// Find all text blocks
$es = $html->find('text');
// Find all comment (<!--...-->) blocks
$es = $html->find('comment');
// Find all <li> in <ul>
foreach($html->find('ul') as $ul)
{
foreach($ul->find('li') as $li)
{
// do something...
}
}
// Find first <li> in first <ul>
$e = $html->find('ul', 0)->find('li', 0);

## How to access the HTML element's attributes?

Top

- Get, Set and Remove attributes
- Magic attributes
- Tips

// Get a attribute ( If the attribute is non-value attribute (eg. checked, selected...), it will returns true or false)
$value = $e->href;
// Set a attribute(If the attribute is non-value attribute (eg. checked, selected...), set it's value as true or false)
$e->href = 'my link';
// Remove a attribute, set it's value as null!
$e->href = null;
// Determine whether a attribute exist?
if(isset($e->href))
echo 'href exist!';
// Example
$html = str_get_html("<div>foo <b>bar</b></div>");
$e = $html->find("div", 0);
echo $e->tag; // Returns: " div"
echo $e->outertext; // Returns: " <div>foo <b>bar</b></div>"
echo $e->innertext; // Returns: " foo <b>bar</b>"
echo $e->plaintext; // Returns: " foo bar"

Attribute Name | Usage
--- | ---
$e->tag | Read or write the tag name of element.
$e->outertext | Read or write the outer HTML text of element.
$e->innertext | Read or write the inner HTML text of element.
$e->plaintext | Read or write the plain text of element.

// Extract contents from HTML
echo $html->plaintext;
// Wrap a element
$e->outertext = '<div class="wrap">' . $e->outertext . '<div>';
// Remove a element, set it's outertext as an empty string
$e->outertext = '';
// Append a element
$e->outertext = $e->outertext . '<div>foo<div>';
// Insert a element
$e->outertext = '<div>foo<div>' . $e->outertext;

## How to traverse the DOM tree?

Top

- Background Knowledge
- Traverse the DOM tree

// If you are not so familiar with HTML DOM, check this link to learn more...
// Example
echo $html->find("#div1", 0)->children(1)->children(1)->children(2)->id;
// or
echo $html->getElementById("div1")->childNodes(1)->childNodes(1)->childNodes(2)->getAttribute('id');
You can also call methods with Camel naming convertions.

Method | Description
--- | ---
mixed $e->children ( [int $index] ) | Returns the Nth child object if index is set, otherwise return an array of children.
element $e->parent () | Returns the parent of element.
element $e->first_child () | Returns the first child of element, or null if not found.
element $e->last_child () | Returns the last child of element, or null if not found.
element $e->next_sibling () | Returns the next sibling of element, or null if not found.
element $e->prev_sibling () | Returns the previous sibling of element, or null if not found.

## How to dump contents of DOM object?

Top

- Quick way
- Object-oriented way

// Dumps the internal DOM tree back into string
$str = $html->save();
// Dumps the internal DOM tree back into a file
$html->save('result.htm');
// Dumps the internal DOM tree back into string
$str = $html;
// Print it!
echo $html;

## How to customize the parsing behavior?

Top

- Callback function

// Write a function with parameter "$element"
function my_callback($element) {
// Hide all <b> tags
if ($element->tag=='b')
$element->outertext = '';
}
// Register the callback function with it's function name
$html->set_callback('my_callback');
// Callback function will be invoked while dumping
echo $html;
Author: S.C. Chen (me578022@gmail.com)
Original idea is from Jose Solorzano's HTML Parser for PHP 4.
Contributions by: Contributions by: Yousuke Kumakura, Vadim Voituk, Antcs