function defineReactive(obj, key, val) { Object.defineProperty(obj, key, { enumerable: true, configurable: true, get: function() { console.log('get'); return val; }, set: function(newVal) { console.log('set'); val += newVal; } }); } let obj = {name: '成龙大哥', say: '：其实我之前是拒绝拍这个游戏广告的，'}; Object.keys(obj).forEach(k => { defineReactive(obj, k, obj[k]); }); console.log(obj.name + obj.say); // obj.say = '后来我试玩了一下，哇，好热血，蛮好玩的'; // console.log(obj.name + obj.say);