this function could get each meta of html content , and stripped all js and css. 
<?php
function get_meta_data($content)
{
    $content = strtolower($content);
    $content = preg_replace("'<style[^>]*>.*</style>'siU",'',$content);  $content = preg_replace("'<script[^>]*>.*</script>'siU",'',$content); $split = explode("\n",$content);
    foreach ($split as $k => $v)
    {
        if (strpos(' '.$v,'<meta')) {
             preg_match_all(
"/<meta[^>]+(http\-equiv|name)=\"([^\"]*)\"[^>]" . "+content=\"([^\"]*)\"[^>]*>/i",
$v, $split_content[],PREG_PATTERN_ORDER);;
        }
    }
    return $split_content;
}
?>