localStorage.prototype为null

Ian*_*vis 6 html5 local-storage

我正在尝试使用以下内容扩展localStorage ...

localStorage.prototype.setItem2 = function(key,value) {
    localStorage.setItem(key,value);
}
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我得到"localStorage.prototype为null".我这样做了吗?谢谢!

Jim*_*lle 9

localStorage是Storage对象的一个​​实例.试试Storage.prototype.setItem2Object.getPrototypeOf(localStorage).setItem2