App\Repositories\CaptchaRepository::make_rand PHP Method

    public function make_rand($length = "32")
    {
        $str = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890";
        $result = "";
        for ($i = 0; $i < $length; $i++) {
            $num[$i] = rand(0, 61);
            $result .= $str[$num[$i]];
        }
        return $result;
    }