Question

我一直在创建我的第一个Facebook应用程序，其中一个代码示例似乎不起作用。我有最新的PHP SDK：这个php和html代码在下面

我的代码：

<?php
require("facebook-php-sdk/src/facebook.php");
$app_id = "257964450938655";
$auth_url = "http://www.facebook.com/dialog/oauth?client_id=" . $app_id . "&redirect_uri=" . urlencode("http://apps.facebook.com/orangepicker/") . "&scope=email";
$signed_request = $_REQUEST["signed_request"];
list($_encoded_sig, $_payload) = explode('.', $signed_request, 2);
$_data = json_decode(base64_decode(strtr($_payload, '-_', '+/')), true);
?>

<!DOCTYPE html>
<html lang="en" xmlns:fb="http://www.facebook.com/2008/fbml">
    <head>
        <meta charset="utf-8" />
        <title>Orange Picker</title>
    </head>
    <body>
        <?php if (empty($data["user_id"])):
            echo("<script>top.location.href='" . $auth_url . "'</script>");
            echo("<div align=\"center\"><a href=\"" . $auth_url . "\" target=\"blank\">Authorize This Application</a></div>");
            echo($data["user_id"]);?>
        <?php else: ?>
        <noscript><div align="center">You need JavaScript enabled to use this app.</div></noscript>
        <div align="center"><img src="Resources/tree.png" usemap="#treemap" /></div>
        <map name="treemap">
            <area shape="circle" coords="22,29,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="37,26,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="55,22,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="75,14,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="93,16,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="112,13,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="128,12,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="146,17,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="166,26,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="182,33,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="194,42,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="208,57,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="222,70,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="234,88,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="236,110,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="223,123,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="208,134,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="193,146,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="177,155,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="161,165,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="144,171,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="125,171,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="106,166,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="84,162,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="70,158,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="55,151,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="42,136,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="29,123,10" onclick="OrangeClick()" alt="Orange" />
            <area shape="circle" coords="20,107,10" onclick="OrangeClick()" alt="Orange" />
        </map>
        <div align="center" style="font-size:large;"><span id="waitTime"></span> <span id="TotalOranges"></span> <span id="TotalCarts"></span></div>
        <script type="text/javascript">
            function OrangeClick() {

            }
        </script>
        <div align="center">Copyright&#169; Neil Flodin <?php echo date("Y"); ?></div>
        <?php endif; ?>
    </body>
</html>

Facebook示例代码（来自here）：

<?php 

     $app_id = "YOUR_APP_ID";

     $canvas_page = "YOUR_CANVAS_PAGE_URL";

     $auth_url = "http://www.facebook.com/dialog/oauth?client_id=" 
            . $app_id . "&redirect_uri=" . urlencode($canvas_page);

     $signed_request = $_REQUEST["signed_request"];

     list($encoded_sig, $payload) = explode('.', $signed_request, 2); 

     $data = json_decode(base64_decode(strtr($payload, '-_', '+/')), true);

     if (empty($data["user_id"])) {
            echo("<script> top.location.href='" . $auth_url . "'</script>");
     } else {
            echo ("Welcome User: " . $data["user_id"]);
     } 
 ?>

我的代码只是在运行时不断刷新页面。任何有FB PHP SDK经验的人都知道为什么？

Answer 1

画布网址（redirect_uri）应指向您托管应用程序的位置，而不是指向facebook网址。即您在画布的facebook开发人员设置中添加的相同网址！

而且，这一行：

$_data = json_decode(base64_decode(strtr($_payload, '-_', '+/')), true);

应该没有下划线：

$data = json_decode(base64_decode(strtr($_payload, '-_', '+/')), true);

稍后您会检查$data的内容，看看用户是否经过身份验证。

Answer 2

问题是您在设置变量时已将变量定义为$_data，但在使用$data进行检查时将其称为empty()。由于这将导致它始终返回true，因此您的代码将始终输出JavaScript重定向。

我猜你以前也验证了这个应用程序。这意味着一旦您被重定向到Facebook，您立即被重定向回来（因为您已经登录）。因此，无限循环。

注意：

您不应在$之后加下划线，否则可能会混淆使用PHP的一个特殊变量。
您应该修改Facebook's PHP SDK文档。它
似乎很多浮动的例子都不是最新的他们的SDK版本。

Facebook PHP SDK示例无效

2 个答案: