我有一个要循环的对象。在我循环对象之前，我决定将值存储在单独的变量中，为了这样做，我使用对象符号来获取值..我对“选项”和“行”进行了未定义-这两个访问有什么问题？
或者任何人告诉我访问这些节点的正确方法。
我目的是：

var ob = {
   "DashBoard":[

    {"title":"DashBoard"},
    {"widget":[{"slide":"To do"},{"slide":"Teamspace"},{"slide":"Recent Activity"}]},
    {"activity":[
        {"option":[{"show":"Volvo"},{"show":"Benz"},{"show":"Honda"}]},
        {"rows":[

            {"title":"Advert1", "text":"sample text1", "date":"22-06-2013"},
            {"title":"Advert2", "text":"sample text2", "date":"22-06-2014"},
            {"title":"Advert3", "text":"sample text3", "date":"22-06-2015"},
            {"title":"Advert4", "text":"sample text4", "date":"22-06-2016"},
            {"title":"Advert5", "text":"sample text5", "date":"22-06-2017"}

        ]}
    ]}

   ]
} 

var title =  ob.DashBoard[0], widget= ob.DashBoard[1], option = ob.DashBoard[2]["option"], rows = ob.DashBoard[2]["rows"];

console.log(option); //undefined
console.log(rows); //undefined

我在两种情况下都得到了未定义的结果...
fiddle here