PHP_TP3/models/m_hello.php

<?php

require_once("lib/getPDD.php");

$bdd = getPDO();

if ($bdd instanceof PDO) {
    try {
        $req = $bdd->prepare("SELECT * FROM Utilisateur WHERE nom = ?");
        $req->execute(array($username));

        if (!$user = $req->fetch())
            $alert = choixAlert("login");
    } catch (Exception $e) {
        $alert = choixAlert("query");
    }
} elseif ($bdd instanceof Exception)
    $alert = choixAlert("connexion");