key值为数字字符的对象，按数字大小顺序排序|自定义obj.sort函数|为对象排序

　　var helper = {　　sort:function(data){ //｛“20141216”：｛｝，“20141217”：｛｝｝按大小排序,
        var arr1 = [],arr2=[],self = this;
        for(var key in data){
            arr1.push(key);
        }
        arr1.sort();
        for(var i=0;i<arr1.length;i++){
            var date = arr1[i];
            var o = self._clone(data[date]);
            o.date = arr1[i];
            o.flag = o.hasOwnProperty(‘img‘);
            arr2.push(o);
        }
        return arr2;
    }

}