php - 验证 - 如果语句不起作用

Question

我正在尝试使用 Javascript 进行简单的表单验证。在本例中，我有一个电子邮件文本输入，如果该电子邮件不是有效电子邮件或电子邮件地址已被占用，我希望它出错。有效的电子邮件部分错误正常，但电子邮件地址已被占用的部分始终会通过。

这是我的脚本代码

<script src="http://code.jquery.com/jquery-latest.min.js"></script>
<script>
function valemail() 
{
var email = $('input#email').val();
var atpos=email.indexOf("@");
var dotpos=email.lastIndexOf(".");
if (atpos<1 || dotpos<atpos+2 || dotpos+2>=email.length)
    {
    document.getElementById("email").style.border="3px solid red";
    document.getElementById('email_error').style.display = 'block'; 
    document.getElementById('email_error').innerHTML = 'A valid email address is required';
    } else {
if ($.trim(email) != '') 
{

    $.post('../ajax/registeremail.php', {email: email}, function(data) 
    {
        if ($.trim(data) == 'That email address is already in use. If you have created an account, 
<a href="../login.php">Login</a>') 
        {
            document.getElementById("email").style.border="3px solid red";
            document.getElementById('email_error').style.display = 'block'; 
            $('div#email_error').text(data);
        } else {
            document.getElementById("email").style.border="3px solid #33FF33";
            document.getElementById('email_error').style.display = 'none'; 
        }
    });
   }
}}
 </script>

我的 registeremail.php 文件可以独立工作，并且是:

<?php
include('../init.php');
//email validation
if (isset($_POST['email']) === true && empty($_POST['email']) === false) {
$email = $_POST['email'];

if (email_exists($email) === true) {
echo('That email address is already in use. If you have created an account, <a>Login</a>');
} else {
echo('Good');
}
?>

实际的文本输入和div代码是

      <input class="input" type="text" tabindex="2" placeholder="Email*" style="height:20px;" name="email"  
id="email" onchange="valemail()">
<div id="email_error"></div>

有谁知道为什么会这样吗？我真的很困惑。

Answer 1

问题是你在 PHP 中 echo 的是

That email address is already in use. If you have created an account, <a>Login</a>

你在 JavaScript 中检查的是

That email address is already in use. If you have created an account, <a href="../login.php">Login</a>

即它们不一样...

我建议您返回 1 (true) 或 0 (false)，然后使用 JavaScript 输出文本..类似于

if (email_exists($email) === true) {
   echo('0');
} else {
   echo('1');
}

那么你的 JavaScript 会是这样的

if ($.trim(data) == '0') {
    document.getElementById("email").style.border = "3px solid red";
    document.getElementById('email_error').style.display = 'block';
    $('div#email_error').text('That email address is already in use. If you have created an account,<a href="../login.php">Login</a>');
} else {
    document.getElementById("email").style.border = "3px solid #33FF33";
    document.getElementById('email_error').style.display = 'none';
}