jquery的$.each方法解决了有索引特征js对象的遍历

var flag = {};

flag[0] = true;

flag[1] = false;

flag[2] = true;

$.each(flag, function(index, element) {

if(index != 2) {
flag[index]=false;
}

});

而另一种遍历方式for(var every in obj)常用在对象值判断上

for(var every in obj) {

if(every == 'aaa') {every = 'bbb'}

}