jQuery驗證插件addMethod

Question

我想用下面的代碼添加一個新的方法到jQuery驗證插件。我的目標是檢查電子郵件地址是否已經存在於數據庫（MySQL）中。如果是，它會通知用戶註冊另一個電子郵件地址。不知何故，總是返回的結果是「電子郵件已被採納」。

這些都是validate.js代碼：

$(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'); 
    } 
}); 
}); 

而這些都是在我的PHP文件中的代碼：

<?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

你不能完全用自定義的方法，因爲這樣做這裏你需要驗證插件來知道這是一個遠程（或更重要的是一個異步）請求。

幸運的是，它具有幫助的內置功能。取而代之的是自定義的方法，你可以在這裏使用remote，所以完全的自定義方法的離開，並改變了這一點：

uniqueEmail: true 

此：

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

的錯誤信息，那麼添加到messages是這樣的：

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

而且改變你的PHP端匹配，返回true或false，像這樣：

<?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 
    } 
?>