crawl site and retrieve only links that start with http:// - php

Question

I am using the following code to retrieve links from the <a> tag but would like to make some adjustments.
Would like to only return links that begin with "http://"
Would like to include links to image and script references that include "http://"
Would be even better if it can return links for all tags as long as it begins with "http://"
Here is the current code:
<?php
$html = file_get_contents('http://mattressandmore.com/in-the-community/');
$dom = new DOMDocument();
#$dom->loadHTML($html);
// grab all the links on the page
$xpath = new DOMXPath($dom);
$hrefs = $xpath->evaluate("/html/body//a");
for ($i = 0; $i < $hrefs->length; $i++) {
$href = $hrefs->item($i);
$url = $href->getAttribute('href');
echo $url.'<br />';
}
?>

Answer 1

You will need to apply starts-with function to href attribute of a element :)
Check some reference and you will get idea, here is the code:
...
$hrefs = $xpath->evaluate("/html/body//a[starts-with(#href, \"http:\")]");
...
Full code:
<?php
$html = file_get_contents('http://mattressandmore.com/in-the-community/');
$dom = new DOMDocument();
#$dom->loadHTML($html);
// grab all the links on the page
$xpath = new DOMXPath($dom);
$hrefs = $xpath->evaluate("/html/body//a[starts-with(#href, \"http:\")]");
for ($i = 0; $i < $hrefs->length; $i++) {
$href = $hrefs->item($i);
$url = $href->getAttribute('href');
echo $url.'<br />';
}
?>
Similarly you can try for img tag with src starting with "http://" and script href attribute too.
...
$hrefs = $xpath->evaluate("/html/body//img[starts-with(#src, \"http:\")]");
...