How to display the found matches of preg_match function in PHP?

I am using the following to check if links exist on file.php:

$fopen = fopen('file.php', 'r');

$fread = fread($fopen, filesize('file.php'));

$pattern = "/^<a href=/i";

if (preg_match($pattern, $fread)) {
    echo 'Match Found';
} else {
    echo 'Match Not Found';
}

if I echo preg_match($pattern, $fread) I get a boolean value, not the found matches. I tried what was on the php.net manual and did th开发者_高级运维is:

preg_match($pattern, $fread, $matches);

then when I echoed $matches I got "Array" message. So I tried a foreach loop and when that didn't display anything I tried $matches[0] and that too outputted nothing.

So how does one go about displaying the matches found?

EDIT

Here is the only content of file.php:

<a href="">Hello</a>

<a href="http://google.com">Hello</a>

<a href="/index.html">Hello</a>

To get the links you're looking for to actually show up you need to have match groups within your regular expression: (note I also added the m modifier to deal with multiple lines)

$pattern = "/^<a href=(.*?)>/im";

Then, if you just want to visualize the contents of that match result array for debugging you can use print_r.

if (preg_match_all($pattern, $fread, $matches)) {
    echo 'Match Found';
    print_r($matches);
} else {
    echo 'Match Not Found';
}

A better approach is to use DOMDocument to parse the HTML document

$dom = new DomDocument;
$dom->loadHTMLFile('file.php');
$nodes = $dom->getElementsByTagName('a');
foreach ($nodes as $node)
{
  echo simplexml_import_dom($node)->asXML(), '<br/>';
}