Analizzare testo e sottilineare parole non presenti nel database

[badaze]

Prova cosi. Non testato.

function wrongwords($text)
{
$words = str_word_count($text,1);
    $conn = mysqli_connect('127.0.0.1','root','','esame') or die("Connection failed: " . $conn->connect_error);
    foreach ($words as $word)
    {
    $query = mysqli_query($conn,"SELECT * FROM vocabolario WHERE vocabolo like '%$word%'");
        if(mysqli_num_rows($query) == 0) 
        {
         $t= "<u>$word</u>";
         $text = preg_replace("/\b$word\b/", $t, $text);
        }
    }
     echo $text;
    $conn->close();
}