小编Joh*_*son的帖子

这更像是一个JavaScript Closure问题而不是Firebase问题.在以下代码中,Firebase回调未识别父作用域中的变量myArr.

function show_fb() {
    var myArr = [];
    var firebase = new Firebase('https://scorching-fire-6816.firebaseio.com/');
    firebase.on('child_added', function(snapshot) {
        var newPost = snapshot.val();
        myArr.push(newPost.user);
        console.log(myArr); // works
    });
    console.log(myArr); // doesn't work. myArr in the firebase.on callback is
                        // not altering myArr
    return myArr;
};