js对象添加属性

var obj = new Object()

obj.keyName = "something"

let obj = {'a1':'a1'};

obj['a2'] = 'a2';

console.log(obj);//输出{'a1':'a1','a2':'a2'};

function Person() {}

var person = new Person();

Person.prototype.name = '张三';

Person.prototype.say = function() {alert(this.name)};

person.say();