Something

$test = explode("\n", stripslashes($_POST['meta']));
$meta = get_meta_tags($file);
	    
foreach ($meta as $value => $key) 
{
	$replace = preg_grep('/<meta[^>]*'.$value.'[^>]*content="([^>]+)"[^>]*>|Ui/', $test);
	$pattern = '/<meta[^>]*'.$value.'[^>]*content="([^>]+)"[^>]*>|Ui/';
	$html = preg_replace($pattern, $replace[0], $html);
	  		
	//$replaceKey = array_search($metaTag, $test);
}