/** * JS AOP方法拦截方法,只要返回false，后边的方法就不再执行 * 调用示例 ： *         func = func.before(beforefn).after(afterfn); *         func(); */Function.prototype.before = function(beforefn){    var _self = this;    return function(){        if(beforefn.apply(this,arguments) === false){            return false;        }        return _self.apply(this,arguments);    }}Function.prototype.after = function(afterfn){    var _self = this;    return function(){        var ret = _self.apply(this,arguments);        if(ret === false){            return false;        }        afterfn.apply(this,arguments);        return ret;    }}