erp_yzx/app/admin/controller/Index.php

<?php
declare (strict_types = 1);
namespace app\admin\controller;

use app\BaseController;
use think\facade\View;

class Index extends BaseController
{
    public function index()
    {
        View::assign('first', '1');

        return view();
    }

    public function hello($name = 'ThinkPHP6')
    {

        return 'hello,' . $name;
    }
}