PHP - 错误ASCII = 16状态= 0输入中的意外字符

Question

我第一次遇到这个错误，似乎无法调试它。我的代码涉及此错误如下：

<?php
session_start();
$accountUsername = $_POST["username"];
$accountEmail = $_POST["email"];
$accountPassword = $_POST["password"];
$accountPasswordConfirm = $_POST["password-confirm"];
$recaptchaResponse = $_POST["g-recaptcha-response"];
$secretRecaptcha = "XXXXXXXXXXXXXXXX";

// Send Request Of Recaptcha To Google Servers
$verifyResponse = file_get_contents('https://www.google.com/recaptcha/api/siteverify?secret='.$secretRecaptcha.'&response='.$recaptchaResponse);
$recaptchaValidation = json_decode($verifyResponse, true);

// Validate Recaptcha Response
//if ($recaptchaValidation["success"] == false) {
    //echo "error:You must solve the reCAPTCHA verification";
    //exit();
//}

// Validate Email Address
$accountEmaili = str_replace("@", "", $accountEmail); $accountEmaili = str_replace(".", "", $accountEmaili);
if (filter_var($accountEmail, FILTER_VALIDATE_EMAIL) && ctype_alnum($accountEmaili)) {
} else {
    echo "error:You must enter a valid email address";
    exit();
}
if (strlen($accountEmail) >= 5 && strlen($accountEmail) <= 400) {
} else {
    echo "error:You must enter a valid email address";
    exit();
}

// Validate Username
if (strlen($accountEmail) >= 8 && $accountEmail <= 14) {
} else {
    echo "error:Your username must be 8-14 characters";
    exit();
}

我试图改变一些东西，但没有任何作用，我不知道这个错误代码也意味着什么。任何人都可以帮我调试这个问题，非常感谢。

错误：警告：输入中出现意外的字符：'/（ASCII = 16）state = 0 in / home / nodebase / public_html / Web App / Backend / UserPortal / Register / Create Account.php on 27行

警告：输入中出现意外字符：'/（ASCII = 16）state = 0 in / home / nodebase / public_html / Web App / Backend / UserPortal / Register / Create Account.php on 27行

第27行= if (strlen($accountEmail) >= 5 && strlen($accountEmail) <= 400) {