在Yii中显示来自多个表PHP和MySQL的数据

// User.php
class User extends \yii\db\ActiveRecord
{
    public static function tableName()
    {
        return 'user';
    }
}

// Order.php
class Order extends \yii\db\ActiveRecord
{
    public static function tableName()
    {
        return 'order';
    }
}

// UserController.php
public function actionIndex()
{
    $users = User::find()->all();

    return $this->render('index', [
        'users' => $users,
    ]);
}

// index.php
foreach ($users as $user) {
    echo $user->name;

    foreach ($user->orders as $order) {
        echo $order->order_number;
    }
}

// User.php
public function getOrders()
{
    return $this->hasMany(Order::class, ['user_id' => 'id']);
}