Question

以下是我正在使用的内容，我对其进行了简化：

if (response.authResponse) {
    FB.api('/me', function(response) {
        response.id;

        user_id = response.id; // I thought I could at least access it below if it was defined globally...

    });     

    var friend_list = [];
    FB.api('/me/friends', function(response) {

        $.each(response.data,function(index,friend) {

            friend_list.push(friend.id);

        });

        user_friend_list = friend_list.toString();

    });  


    alert("user id:"+user_id+"friend list:"+user_friend_list); // Here is where I would like these two variables to show up

} else {
    //user cancelled login or did not grant authorization

}

可能是出于一些明显的原因（由于我的javascript和jquery不好）我无法捕获变量。如果你提供答案，请解释一下，这样我就可以获得洞察力和学习。

Answer 1

试试这个。

if (response.authResponse) {
    FB.api('/me', function(data) {
        var user_id = data.id;
        FB.api('/me/friends', function(response) {
            var friend_list = [];
            for (i = 0; i < response.data.length; i++) {
                friend_list.push(response.data[i].id);
            }
            //user_friend_list = friend_list.join(",");
            alert("user id:" + user_id + "friend list:" + friend_list.join(","));
        });
    });
}
else {
    alert("no access granted");
}

改变了一些代码。如果您对此解决方案有疑问，请发表评论。

Answer 2

您可以假设这些值的唯一位置是作为第二个参数提供的回调函数。这是因为api（）方法是异步的。

您可以使用以下代码结束：

if (response.authResponse) {
    FB.api('/me', function (response) {
        // Now first asyncrhonous call is over, let's do the second one
        response.id;
        user_id = response.id; // I thought I could at least access it below if it was defined globally...
        var friend_list = [];
        FB.api('/me/friends', function (response) {
            // Now second asynchronous call is over, we have both values defined.
            $.each(response.data, function (index, friend) {
                friend_list.push(friend.id);
            });

            user_friend_list = friend_list.toString();


            alert("user id:" + user_id + "friend list:" + user_friend_list); // Here is where I would like these two variables to show up
        });
    });

} else {
    //user cancelled login or did not grant authorization
}

使用FB API Jquery，Javascript的javascript变量的范围

2 个答案: