我最近编写了这段代码来向一位朋友解释 Facebook 登录功能。每行代码都有详细的注释。我不确定这是否是最好的方法。但这很容易理解。
<?php
//include Facebook library File
include_once "src/facebook.php";
//Application Configurations
//Declare variables app_id,app_secret, we get app_id,app_secret values from app dashboard.
$app_id = "xxxxxxxxxxxxxxxxxx";
$app_secret = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
// Create our application instance
//we create $facebook instance and would use it to access various Facebook library functions
$facebook = new Facebook(array(
'appId' => $app_id,
'secret' => $app_secret,
));
?>
<html>
<head>
</head>
<body>
<?php
// Get User ID
$user = $facebook->getUser();
// $facebook->getUser() is a function which would return a user id if someone is
// logged in on Facebook currently (In some other window or tab)
// We may or may not have this data based
// on whether the user is logged in.
// If we have a $user id here, it means we know
// the user is logged into Facebook,
// but we don’t know if the user has authorized our application.
// i.e whether user has already given our app permissions to access his data or not
if ($user) {
/*
* Facebook user retrieved
* $user : Holds the Facebook Users unique ID
* */
try {
// We try to get users data assuming he has authoized are app if we dont get data we display login button in catch block.
$userinfo = $facebook->api('/me');
echo "<br/>User id : ".$userinfo['id'];
echo "<br/>Name : ".$userinfo['name'];
echo "<br/>Gender : ".$userinfo['gender'];
echo "<br/>Email : ".$userinfo['email'];
echo "<br/>Location : ".$userinfo['location']['name'];
echo "<br/>Image : <img src='https://graph.facebook.com/".$userinfo['id']."/picture' >";
echo "<br/><br/><br/>Similarly we can get lot more information about user like work experience, dob etc more details would be shared later /We use this data to prefill registration form for user. ";
echo "<br/><br/>Below is dump of entire array which shows all available data it carries<br/><br/>";
echo '<pre>';
var_dump($userinfo);
echo '</pre>';
//Similarly we can get lot more information about user like work experience, dob etc more details would be shared later
//We use this data to prefill registration form for user.
} catch (FacebookApiException $e) {
// Display Facebook login button - Requires Facebook JavaScript SDK (Below)
echo '<fb:login-button show-faces="true" width="200" scope="email,user_photos"></fb:login-button>'."\n";
$user = NULL;
}
} else {
// No user logged in currently Display Facebook login button - Requires Facebook JavaScript SDK (Below)
echo '<fb:login-button show-faces="false" width="200" scope="email,user_photos"></fb:login-button>'."\n";
}
?>
<!--Below code is required to use FAcebook Javascript SDK/Library, Before this we have been using Facbeook PHP-SDK/Library -->
<div id="fb-root"></div> <!-- A div element with id "fb-root" is required. Facebook JS SDK will auto create this element if it doesn't exist , But we will anyways create it-->
<script>
// window.fbAsyncInit will execute code within it asynchronously i.e without affecting the load time.
window.fbAsyncInit = function () {
//Below code Initializes Javacript SDK, appid is same as one defined in fbaccess.php
FB.init({
appId : '<?=$app_id?>',
cookie : true,
xfbml : true,
oauth : true
});
//Below code tells the script to refresh whenever user logins or logouts.
FB.Event.subscribe('auth.login', function (response) { window.location.reload(); });
FB.Event.subscribe('auth.logout', function (response) { window.location.reload(); });
};
// Copy paste code to load the Facebook JavaScript SDK into the page
(function(){var e=document.createElement('script');e.async=true;e.src=document.location.protocol+'//connect.facebook.net/en_US/all.js';document.getElementById('fb-root').appendChild(e);}());
</script>
</body>
</html>
在 Javascript 中，您可以调用这样的函数：
function login(){
FB.getLoginStatus(function(response) {
if (response.authResponse) {
alert(response.authResponse.userID);
//Authenticated user.
} else {
// Unauthenticated user display authentication popup
FB.login(function(response) {
if (response.authResponse) {
alert(response.authResponse.userID);
//User authenticated.
}
else{
alert("Please allow authentication to proceed!!");
}
}, {scope:'email'});
}
});
}