Can PHP write crawlers? (Example of PHP implementation of crawler technology)

Can php be used as a crawler? Can I write a crawler in PHP? When it comes to web crawlers, everyone must first think of Python as a crawler. In fact, PHP can also be used to implement web crawler functions!

Now we will introduce to you how to use PHP to make a simple web crawler!

It’s actually very easy to get a tag from another website and parse the data. This can be done through a PHP function file_get_contents as shown below:

<?php
$webpage = file_get_contents(&#39;http://www.tonylea.com&#39;);
?>

Now, the variable $webpage contains all of http://www.tonylea.com tag(source).

Basically, if we want to parse the data, we do this:

<?php
$url = &#39;http://www.tonylea.com&#39;;
$webpage = file_get_contents($url);
function get_images($page)
{
     if (!empty($page)){
          preg_match_all(&#39;/<img([^>]+)\/>/i&#39;, $page, $images);
          return !empty($images[1]) ? $images[1] : FALSE;
     }
}
function get_links($page)
{
     if (!empty($this->markup)){
          preg_match_all(&#39;/<a([^>]+)\>(.*?)\<\/a\>/i&#39;, $this->markup, $links);
          return !empty($links[1]) ? $links[1] : FALSE;
     }
}

$images = get_images($webpage);
foreach($images as $image)
{
     echo $image.&#39;<br />&#39;;
}
?>

In the above example, we got the tag from the specified URL and got 'a' tag and the value contained in the 'img' tag. The code then prints out the data in the "img" tag. With more parsing, you can display images and links obtained from crawled or crawled pages.

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