jQuery验证插件addMethod

Question

我想用下面的代码添加一个新的方法到jQuery验证插件。我的目标是检查电子邮件地址是否已经存在于数据库（MySQL）中。如果是，它会通知用户注册另一个电子邮件地址。不知何故，总是返回的结果是“电子邮件已被采纳”。

这些都是validate.js代码：

$(document).ready(function(){ 
$.validator.addMethod("uniqueEmail", function(value, element) { 
    $.ajax({ 
     type: "POST", 
     url: "availability.php", 
     data: value, 
     success: function(exist) 
     { 
     if(exist>0) { 
     return true; 
     } return false; 
     } 
    }); 
} ,"Email is already taken"); 
$('#signup form').validate({ 
    rules: { 
    firstname: { 
    required: true, 
    minlength:3 
    }, 
    lastname: { 
    required: true, 
    minlength: 3 
    }, 
    affiliation: { 
    required: true, 
    }, 
    occupation: { 
    required: true, 
    }, 
    email: { 
    required: true, 
    email: true, 
    uniqueEmail: true 
    }, 
    password: { 
    minlength: 6, 
    required: true 
    }, 
    repassword: { 
    equalTo: "#password" 
    } 
    }, 
    messages: { 
    firstname: { 
    minlength: "Your first name should be more than 3 characters" 
    }, 
    lastname: { 
    minlength: "Your last name should be more than 3 characters" 
    }, 
    }, 
    success: function(label) { 
    label.text('OK!').addClass('valid'); 
    } 
}); 
}); 

而这些都是在我的PHP文件中的代码：

<?php 

include_once $_SERVER['DOCUMENT_ROOT'] . '/braddclient/includes/magicquotes.inc.php'; 
include $_SERVER['DOCUMENT_ROOT'] . '/braddclient/includes/db.inc.php'; 

$email = strtolower($_POST['email']); 
$email = mysqli_real_escape_string($link, $email); 
$sql = "SELECT * FROM bradduser WHERE email='$email'"; 
$result = mysqli_query($link, $sql); 
$num = mysqli_num_rows($result); 

echo $num; 

?> 

Answer 1

你不能完全用自定义的方法，因为这样做这里你需要验证插件来知道这是一个远程（或更重要的是一个异步）请求。

幸运的是，它具有帮助的内置功能。取而代之的是自定义的方法，你可以在这里使用remote，所以完全的自定义方法的离开，并改变了这一点：

uniqueEmail: true 

此：

remote: { url: "availability.php", type: "post" } 

的错误信息，那么添加到messages是这样的：

email: { remote: "Email is already taken" } 

而且改变你的PHP端匹配，返回true或false，像这样：

<?php 
    include_once $_SERVER['DOCUMENT_ROOT'] . '/braddclient/includes/magicquotes.inc.php'; 
    include $_SERVER['DOCUMENT_ROOT'] . '/braddclient/includes/db.inc.php'; 

    $email = strtolower($_POST['email']); 
    $email = mysqli_real_escape_string($link, $email); 
    $sql = "SELECT * FROM bradduser WHERE email='$email'"; 
    $result = mysqli_query($link, $sql); 
    if(mysqli_num_rows($result) > 0) { 
    echo "false"; //validation fails, email in use 
    } else { 
    echo "true"; //validation passes 
    } 
?>