我目前正在学习使用 Facebook Javascript SDK 来登录用户。起初我不需要询问电子邮件地址，但现在我需要。我尝试了几件从其他人那里读到的东西，但对我没有任何帮助。我之前使用的代码可能有问题吗？添加的最佳方法是scope: "email"什么？
这是我到目前为止使用的代码：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8" />
<title>A Facebook login test!</title>
<link href='http://fonts.googleapis.com/css?family=Roboto' rel='stylesheet' type='text/css'>
<style type="text/css">
h1 {font-family: 'Roboto', sans-serif;}
</style>
</head>
<body>
<div id="fb-root"></div>
<script>
window.fbAsyncInit = function() {
// init the FB JS SDK
FB.init({
appId : '{{ FACEBOOK_APP_ID }}', // App ID from the app dashboard
channelUrl : '{{ DOMAIN }}/channel.html', // Channel file for x-domain comms
status : true, // Check Facebook Login status
cookie : true, // enable cookies to allow the server to access the session
xfbml : true // Look for social plugins on the page
});
// Here we subscribe to the auth.authResponseChange JavaScript event. This event is fired
// for any authentication related change, such as login, logout or session refresh. This means that
// whenever someone who was previously logged out tries to log in again, the correct case below
// will be handled.
FB.Event.subscribe('auth.authResponseChange', function(response) {
// Here we specify what we do with the response anytime this event occurs.
if (response.status === 'connected') {
// The response object is returned with a status field that lets the app know the current
// login status of the person. In this case, we're handling the situation where they
// have logged in to the app.
window.location = "/fblogin";
}
});
};
// Load the SDK asynchronously
(function(d, s, id){
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) {return;}
js = d.createElement(s); js.id = id;
js.src = "//connect.facebook.net/en_US/all.js";
fjs.parentNode.insertBefore(js, fjs);
}(document, 'script', 'facebook-jssdk'));
</script>
<h1>This is the Facebook and Google+ login test.</h1>
<br>
<fb:login-button show-faces="true" width="200" max-rows="1" scope: "email"></fb:login-button>
<br>
为什么没有要求用户让我的应用访问他的电子邮件地址？
在此先感谢大卫。