js 实现 AOP

Function.prototype.before = function (beforefn) {var _self = this;return function () {beforefn.apply(this, arguments);return _self.apply(this, arguments);}};Function.prototype.after = function (afterfn) {var _self = this;return function () {var ret = _self.apply(this, arguments);afterfn.apply(this, arguments);return ret;}};var func = function () {console.log(2);};func = func.before(function () {console.log(1);}).after(function () {console.log(3);});func();