一个成员函数查询()我是一个新手,OOP和尚在测试阶段,能有人指出哪里我的错误是什么? 我收到提示致命错误:未捕获的错误:调用上的空
Fatal error: Uncaught Error: Call to a member function query() on null on the following line:
我已经意识到,DB连接没有被从核心类继承,但我不知道为什么。
$user = $this->db->query("SELECT * FROM users WHERE id='".$user_id."' LIMIT 1");
class.php
class Core {
public $db;
public $domain;
public $settings;
public function getDomain() {
return $this->domain;
}
function __construct($db,$domain) {
$this->db = $db;
$this->domain = $domain;
$this->getSettings();
}
public function getSettings() {
$settings = $this->db->query("SELECT * FROM settings");
$settings = $settings->fetch_object();
$this->settings = $settings;
}
}
class User extends Core {
public $user;
function __construct($user_id) {
$this->setUser($user_id);
}
public function setUser($user_id) {
$user = $this->db->query("SELECT * FROM users WHERE id='".$user_id."' LIMIT 1");
if($user->num_rows >= 1) {
$user = $user->fetch_object();
$this->user = $user;
}
}
的index.php
$core = new Core($db,$domain);
$user = new User($_SESSION['user_id']);
澄清:
我的数据库变量从我的config.php文件通过我包括index.php页面的开始 的config.php
$_db['host'] = 'localhost';
$_db['user'] = 'root';
$_db['pass'] = 'root';
$_db['name'] = 'social';
$db = new mysqli($_db['host'], $_db['user'], $_db['pass'], $_db['name']) or die('MySQL Error');
什么时候开始的会议?该会话数组是否包含一个值? –
是的,会议已经开始。我认为这是事做不被继承了$ DB变量或东西 –
一个正在进行几件事情。您可以在写入$ core = new Core($ db,$ domain)之前展示如何设置变量$ db? – Yolo