对象方法扩展

判断两个值是否完全相等
object.is(NaN,NaN) 返回true

对象合并 object.assign()

const config1={
    host:'localhost',
    port:3306,
    name:'root',
    pass:'root',
    test:'test'
}


const config2={
    host:'http:gui.com',
    port:3322,
    name:'gui.com',
    pass:'iloveyou',
    texs2:'test'
}

object.assign(config1,config2);

后面参数覆盖前面相同的参数值，没有的会新增参数

const school={
    name:'城市'
}

const cities={
    xiaoqu:['北京','上海','深圳']
}

设置原型对象 object.setPrototypeOf(school,cities)

获取原型对象 object.getPrototypeOf(school)