设置中已开启控制器后缀。现在访问测试页面报错，说是模型的类未找到。
http://127.0.0.1/user/add 报错页面如下图

控制器文件 application\index\controller\UserController.php
<?php
namespace app\index\controller;
use app\index\model\User;

class UserController
{
// 新增用户数据
public function add()
{
$user = new User();

$user->nickname = '流年';
$user->email = 'thinkphp@qq.com';
$user->birthday = strtotime('1977-03-05');
if ($user->save()) {
return '用户[ ' . $user->nickname . ':' . $user->id . ' ]新增成功';
} else {
return $user->getError();
}
}
}
?>

模型文件：application\index\model\User.php
<?
namespace app\index\model;
use think\Model;

class User extends Model
{
protected $name = 'user';

protected $connection = [
'type' => 'mysql',
'hostname' => '127.0.0.1',
'database' => 'demo',
'username' => 'root',
'password' => 'root',
'hostport' => '3306',
'params' => [],
'charset' => 'utf8',
'prefix' => 'think_',
'debug' => true,
];
}
?>