正则表达式帮助在PHP中获取标记内容

Question

so I have the code

function getTagContent($string, $tagname) {

    $pattern = "/<$tagname.*?>(.*)<\/$tagname>/";
    preg_match($pattern, $string, $matches);


    print_r($matches);

}

and then I call

$url = "http://www.freakonomics.com/2008/09/24/wall-street-jokes-please/";
$html = file_get_contents($url);
getTagContent($html,"title");

but then it shows that there are no matches, while if you open the source of the url there clearly exist a title tag....

what did I do wrong?

Answer 1

try DOM

$url  = "http://www.freakonomics.com/2008/09/24/wall-street-jokes-please/";
$doc  = new DOMDocument();
$dom  = $doc->loadHTMLFile($url);
$items = $doc->getElementsByTagName('title');
for ($i = 0; $i < $items->length; $i++)
{
  echo $items->item($i)->nodeValue . "
";
}