lanzu_api_2021-12-26/app/Service/v3/Implementations/HelperService.php

<?php

namespace App\Service\v3\Implementations;

use App\Service\v3\Interfaces\HelperServiceInterface;

class HelperService implements HelperServiceInterface
{

    public function makeNumCode($length)
    {
        // 获取验证码
        $codeArr = array_map(function ($item) {
            return mt_rand(0,9);
        }, array_pad([], $length, 0));

        // 返回验证码
        return implode('', $codeArr);
    }
}