//定义被侦听的目标对象 var engineer = { name: 'Joe Sixpack', salary: 50 }; //定义处理程序 var interceptor = { set: function (receiver, property, value) { console.log(property, 'is changed to', value); receiver[property] = value; } }; //创建代理以进行侦听 new Proxy(engineer, interceptor); //做一些改动来触发代理 engineer.salary = 60;//控制台输出:salary is changed to 60 engineer.salary = 50;//控制台输出:salary is changed to 60