抱歉问了一个基本问题。我是php编程新手。我有下面的代码，这是崩溃时，它得到的get\u结果行。我已经测试了我的本地计算机iis安装和工作良好。但当我把它放在主机上运行时，它崩溃了。你能看一下吗？我感谢你的支持。

$servername = "localhost";
    $username = "user";
    $password = "pwd";
    $dbname = "db";
    $conn = new mysqli($servername, $username, $password, $dbname);
    // check conn
    if ($conn->connect_error) {
        die("Connection failed: " . $conn->connect_error);
        exit();
    }
    $stmt = $conn->prepare("select * from catusuarios where userid = ?");
    $stmt->bind_param('s', $_POST["userid"]);
    $stmt->execute();
    $result = $stmt->get_result();
    $user = $result->fetch_object();
    $conn->close();