对象方法扩展

//1. Object.is 判断两个值是否完全相等 
console.log(Object.is(120, 120));// === 
console.log(Object.is(NaN, NaN));// === 
console.log(NaN === NaN);// === 

        //2. Object.assign 对象的合并
const config1 = {
    host: 'localhost',
    port: 3306,
    name: 'root',
    pass: 'root',
    test: 'test'
};
const config2 = {
    host: 'http://atguigu.com',
    port: 33060,
    name: 'atguigu.com',
    pass: 'iloveyou',
    test2: 'test2'
}
console.log(Object.assign(config1, config2));

//3. Object.setPrototypeOf 设置原型对象  Object.getPrototypeof
const school = {
    name: 'study'
}
const cities = {
    xiaoqu: ['北京','上海','深圳']
}
Object.setPrototypeOf(school, cities);
console.log(Object.getPrototypeOf(school));
console.log(school);