php - Parse Website for URLs

Question

Just wondering if someone can help me further with the following. I want to parse the URL on this website:http://www.directorycritic.com/free-directory-list.html?pg=1&sort=pr

I have the following code:

<?PHP  
$url = "http://www.directorycritic.com/free-directory-list.html?pg=1&sort=pr";
$input = @file_get_contents($url) or die("Could not access file: $url"); 
$regexp = "<as[^>]*href=("??)([^" >]*?)\1[^>]*>(.*)</a>"; 
if(preg_match_all("/$regexp/siU", $input, $matches)) { 
// $matches[2] = array of link addresses 
// $matches[3] = array of link text - including HTML code
} 
?>

Which does nothing at present and what I need this to do is scrap all the URL in the table for all 16 pages and would really appreciate some help with how to amend the above to do that and output URL into a text file.

Answer 1

Use HTML Dom Parser

$html = file_get_html('http://www.example.com/');

// Find all links
$links = array(); 
foreach($html->find('a') as $element) 
       $links[] = $element->href;

Now links array contains all URLs of given page and you can use these URLs to parse further.

Parsing HTML with regular expressions is not a good idea. Here are some related posts:

• Using regular expressions to parse HTML: why not?
• RegEx match open tags except XHTML self-contained tags

EDIT:

Some Other HTML Parsing tools as described by Gordon in comments below:

• phpQuery
• Zend_Dom
• QueryPath
• FluentDom