在laravel中创建帮助器？mycodetest

<?php

function generateRandomString($length = 10) {
    $characters = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
    $randomString = '';

    for ($i = 0; $i < $length; $i++) {
        $randomString .= $characters[rand(0, strlen($characters) - 1)];
    }

    return $randomString;
}

"autoload": {
    "files": [
        "app/Helper.php"
    ]
}

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;

class MyController extends Controller
{
    public function generateRandom(Request $request) {
        $randomString = generateRandomString(8);
        return response()->json(['randomString' => $randomString]);
    }
}