自定義一個方法原型，取得json對象某個值

Object.prototype.k = function(n, t){
       var arr = [];   
       for (pro in this) arr.push(pro);
       return t ? arr[n] : this[arr[n]]
}

一個json對象：

var Tabs = {
	"全部":"pages/page1.html",
	"歪歪":"pages/page2.html",
	"照片":"pages/page3.html",
	"表情":"pages/page4.html"
}

alert(Tabs.k(0,0))   //pages/page1.html
alert(Tabs.k(0,1))   //全部
alert(Tabs.k(1,1))   //歪歪