How can I get html webpage charset encode from html as string and not as dom?

How can I get html webpage charset encode from html as string and not as dom?

I get html string like that:

$html = file_get_contents($url);
preg_match_all (string pattern, string subject, array matches, int flags)

but i dont know regex, and I need to find o开发者_如何学Cut webpage charset (UTF-8/windows-255/etc..) Thanks,

preg_match('~charset=([-a-z0-9_]+)~i',$html,$charset);

First thing you have to check the Content-type header.

//add error handling
$f = fopen($url, "r");
$md = stream_get_meta_data($f);
$wd = $md["wrapper_data"];
foreach($wd as $response) {
    if (preg_match('/^content-type: .+?/.+?;\\s?charset=([^;"\\s]+|"[^;"]+")/i',
             $response, $matches) {
         $charset = $matches[1];
         break;
    }
}
$data = stream_get_contents($f);

You can then fallback on the meta element. That's been answered before here.

More complex version of header parsing to please the audience:

if (preg_match('~^content-type: .+?/[^;]+?(.*)~i', $response, $matches)) {
    if (preg_match_all('~;\\s?(?P<key>[^()<>@,;:\"/[\\]?={}\\s]+)'.
            '=(?P<value>[^;"\\s]+|"[^;"]+")\\s*~i', $matches[1], $m)) {
        for ($i = 0; $i < count($m['key']); $i++) {
            if (strtolower($m['key'][$i]) == "charset") {
                $charset = trim($m['value'][$i], '"');
            }
        }
    }
}

you could use

mb_detect_encoding($html);

but it is generally a bad idea. Better use curl instead and look at the Content-Type header.