Javascript angularjs:Push不是一个函数

我有一个JSON对象，如下所示：

var post = {
    "post_id": "1",
    "content": "content",
    "post_author": {
        "id": "12",
        "firstName": "Amelia",
        "lastName": "Earheart",
    },
    "isLiked": false,
    "likes_count": 0,
    "likers": [],
    "comments_count": 0,
    "commenters": [],
    "comments": []
};

vm.userInfo = function() {
    myService.getBasicUserInfo().success(function(data) {
        vm.currentPost.post_author.id = data.id;
        vm.currentPost.post_author.firstName = data.firstName;
        vm.currentPost.post_author.lastName = data.lastName;
    });
};

{"id":"12","firstName":"Amelia","lastName":"Earheart"}

和

post

从前端传递到下面给出的函数

var vm = this;
vm.likePost = function(post) {
    var likedPost = post;
    vm.userInfo();
    likedPost.likers.push(userObject); //Here

    myService.postLike(likedPost).success(function(data) {
        likedPost.isLiked = true;
        likedPost.likes_count++;
        vm.posts = data;
    });
};

但是这样做，我得到一个JavaScript错误，说

push不是
likedPost.likers.push（userObject）行中的函数

vm.userInfo（）
返回
userObject
，如下所示：

var post = {
    "post_id": "1",
    "content": "content",
    "post_author": {
        "id": "12",
        "firstName": "Amelia",
        "lastName": "Earheart",
    },
    "isLiked": false,
    "likes_count": 0,
    "likers": [],
    "comments_count": 0,
    "commenters": [],
    "comments": []
};

vm.userInfo = function() {
    myService.getBasicUserInfo().success(function(data) {
        vm.currentPost.post_author.id = data.id;
        vm.currentPost.post_author.firstName = data.firstName;
        vm.currentPost.post_author.lastName = data.lastName;
    });
};

{"id":"12","firstName":"Amelia","lastName":"Earheart"}

返回的JSON如下所示：

var post = {
    "post_id": "1",
    "content": "content",
    "post_author": {
        "id": "12",
        "firstName": "Amelia",
        "lastName": "Earheart",
    },
    "isLiked": false,
    "likes_count": 0,
    "likers": [],
    "comments_count": 0,
    "commenters": [],
    "comments": []
};

vm.userInfo = function() {
    myService.getBasicUserInfo().success(function(data) {
        vm.currentPost.post_author.id = data.id;
        vm.currentPost.post_author.firstName = data.firstName;
        vm.currentPost.post_author.lastName = data.lastName;
    });
};

{"id":"12","firstName":"Amelia","lastName":"Earheart"}

有人能帮我找出这个问题的原因吗

更新：

{
    "post_id": "12",
    "content": "Content is the content that contains the content",
    "image": "member-default.jpg",
    "created_at": "2016-05-26 14:29:00",
    "post_author": {
        "id": "12",
        "firstName": "Amelia",
        "lastName": "Earheart",
    },
    "isLiked": false,
}

这就是我得到的
console.log（类似于Post）
输出明确指定未定义
likers
。您可以在使用
push（）
方法之前进行验证检查

//if likedPost.likers is not defined, it will define it as an array 
likedPost.likers = likedPost.likers || [];

//Do the push operation
likedPost.likers.push(userObject);

您的
likedPost
对象没有您期望的
likers
数组。在尝试推之前，您可能会看到是否存在这种情况

if (typeof likedPost !== 'undefined')
   likedPost.likers.push(userObject);

在push调用之前，可以添加以下内容：console.log（likedPost）；并发送结果。给我一分钟@silvinust此错误意味着
likers
不是数组。JSON对象的源是什么？也许在构造它或接收它时有错误。你可以简单地把（如果喜欢Post）放进去，因为如果为null或未定义，它将返回false。这就是IE需要快速而痛苦地死去的原因