JavaScript 代码问题 : I am converting object to array

Question

我正在将 JavaScript 对象转换为数组，但结果我得到一个 null

这是我的代码

<div id="a"></div>

Object.prototype.toArray = function(){
    var arr = [];
    for (var i in this) {
        arr.push(this[i]);        
    }
    return arr;
} 

var providers = {
            facebooklike: "Facebook Like",
            facebookrecommend : "Facebook Recommend",
            facebooksend : "Facebook Send",
            twittertweet : "Twitter Tweet",
            linkedinshare : "LinkedIn Share",
            linkedinrecommend : "LinkedIn Recommend",
            googleplusplusone : "Google+ +1",
            googleplusshare : "Google+ Share"
        };

var a = document.getElementById("a");
a.innerHTML = JSON.stringify(providers.toArray());

我的结果是

["Facebook Like","Facebook Recommend","Facebook Send","Twitter Tweet","LinkedIn Share","LinkedIn Recommend","Google+ +1","Google+ Share",null]

这是 fiddle example

Answer 1

添加对自身属性的检查(不是从对象原型(prototype)继承):

Object.prototype.toArray = function(){
    var arr = [];
    for (var i in this) {
        if(this.hasOwnProperty(i))
            arr.push(this[i]);        
    }
    return arr;
}