php - Mysqli 连接返回 null

Question

我正在尝试创建一个 Mysqli 以使用 OOP 从数据库中获取数据。而且我无法从数据库中获取任何数据，当我检查连接时，它返回 null

这是我的 DatabaseHelper 类。

class DatabaseHelper
{

    private $servername;
    private $username;
    private $password;
    private $dbname;

    public function connect()
    {
        $this->servername = "localhost";
        $this->username = "root";
        $this->password = "";
        $this->name = "test";

        $conn = new mysqli($this->servername, $this->username, $this->password, $this->dbname);
        echo '<pre>';
        var_export($conn);
        echo '</pre>';
    }
}

这是连接数据。

mysqli::__set_state(array(
   'affected_rows' => NULL,
   'client_info' => NULL,
   'client_version' => NULL,
   'connect_errno' => NULL,
   'connect_error' => NULL,
   'errno' => NULL,
   'error' => NULL,
   'error_list' => NULL,
   'field_count' => NULL,
   'host_info' => NULL,
   'info' => NULL,
   'insert_id' => NULL,
   'server_info' => NULL,
   'server_version' => NULL,
   'sqlstate' => NULL,
   'protocol_version' => NULL,
   'thread_id' => NULL,
   'warning_count' => NULL,
))

我上面的代码有什么问题导致连接返回 null 吗？

标签： phpmysqli