31.对象方法的扩展
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// 1.Object.is 判断两个值是否完全相等,类似于===,但是又不太一样,比如NaN===NaN
// console.log(Object.is(120, 100));
// console.log(Object.is(NaN, NaN));
// console.log(NaN === NaN);
// console.log(NaN !== NaN);
// 2.Object.assign 对象的合并---也可用于对象的浅拷贝
let config1 = {
host: "localhost",
port: 3306,
name: "root",
password: "root",
test1: "测试1",
};
let config2 = {
host: "https://www.baidu.com",
port: 33060,
name: "百度",
password: 123,
test2: "测试2",
};
console.log(Object.assign(config1, config2)); //后面对象里的属性会把前面对象里同名的属性覆盖掉,不相同的则保留
// 3.Object.setPrototypeOf,Object.getPrototypeOf
let school = {
name: "xxx",
};
let cities = {
address: ["xx1", "xx2", "xx3"],
};
// 此方法不建议这样做,应该在创建对象的时候就把原型设置好,效率高 Object.create(proto, [propertiesObject])
Object.setPrototypeOf(school, cities); //为school设置原型对象为cities
console.log(school);
console.log(Object.getPrototypeOf(school));
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