Object对象
一、定义对象
var obj={}
var obj = new Object()
二、对象属性赋值
三、获取对象属性
1、Object.keys()
2、Object.getOwnPropertyNames()
四、对象属性模型的相关方法
1、Object.getOwnPropertyDescriptor()
2、Object.defineProperty()
Object.defineProperty(obj, prop, descriptor)
3、Object.defineProperties()
Object.defineProperties(obj, props)
4、Object.propertyIsEnumerable()
五、控制对象状态的方法
1、Object.preventExtensions()
2、Object.isExtensible()
3、Object.seal()
4、Object.isSealed()
5、Object.freeze()
6、Object.isFrozen()
六、原型链的相关方法
1、Object.create()
2、Object.getPrototypeOf()
七、Object方法扩展
1、Object.is()
console.log(Object.is(120, 120));
console.log(Object.is(NaN, NaN));
console.log(NaN === NaN);
2、Object.assign()
const config1 = {
host: 'localhost',
port: 3306,
name: 'root',
password: '123'
};
const config2 = {
host: 'http://www.4399.com',
port: '33060',
name: 'root2',
password: '456'
};
console.log(Object.assign(config1, config2));
3、Object.setPrototypeOf()和Object.getPrototypeOf()
const school = {
name: 'GDUF'
};
const cities = {
xiaoqu: ['广州', '肇庆', '清远']
};
Object.setPrototypeOf(school, cities);
console.log(Object.getPrototypeOf(school));
4、Object.keys()
Object.keys(obj);
5、Object.values()
Object.values(obj);
6、Object.entries()
Object.entries(obj);
7、Object.fromEntries()
Object.fromEntries(obj);