JavaScript 对象方法示例

const obj = { a: 1, b: 2, c: 3 };
console.log(object.keys(obj));
// output: ['a', 'b', 'c']

const obj = { a: 1, b: 2, c: 3 };
console.log(object.values(obj));
// output: [1, 2, 3]

const obj = { a: 1, b: 2, c: 3 };
console.log(object.entries(obj));
// output: [['a', 1], ['b', 2], ['c', 3]]

const obj = object.seal({ a: 1 });
console.log(object.issealed(obj));
// output: true

const target = { a: 1 };
const source = { b: 2, c: 3 };
const result = object.assign(target, source);
console.log(result);
// output: { a: 1, b: 2, c: 3 }

const obj = { name: 'khabib' };
object.freeze(obj);
obj.name = 'bob'; // this won't change the value
console.log(obj.name); // output: 'khabib'

const obj = { name: 'alice' };
object.seal(obj);
obj.name = 'bob'; // this will update the value
obj.age = 25; // this won't add a new property
console.log(obj); // output: { name: 'bob' }

const person = {greet() {console.log('hello!');}};
const student = object.create(person);
student.greet();
// output: 'hello!'

const obj = {};
object.defineproperty(obj, 'name', {
value: 'alice',
writable: false });
console.log(obj.name); // 'alice'

const obj = {};
object.defineproperties(obj, {
name: { value: 'cormier', writable: false },
age: { value: 30, writable: true } });
console.log(obj.name); // 'cormier'

const obj = {};
console.log(object.isextensible(obj)); // true
object.preventextensions(obj);
console.log(object.isextensible(obj)); // false

const obj = object.freeze({ name: 'gregor' });
console.log(object.isfrozen(obj));
// output: true

const obj = { name: 'alice' };
console.log(object.hasown(obj, 'name')); // true
console.log(object.hasown(obj, 'age')); // false

const obj = { name: 'alice' };
console.log(obj.hasownproperty('name')); // true
console.log(obj.hasownproperty('age')); // false

const obj = {};
object.preventextensions(obj);
obj.name = 'khabib'; // won't be added
console.log(obj); // {}

const proto = { greet() {console.log('hello!');}};
const obj = {};
object.setprototypeof(obj, proto);
obj.greet(); // 'hello!'

const entries = [['name', 'rock'], ['age', 35]];
const obj = object.fromentries(entries);
console.log(obj); // { name: 'rock', age: 35 }

const obj = {};
const proto = object.getprototypeof(obj);
console.log(proto === object.prototype); // true

const symbol = symbol('id');
const obj = { [symbol]: 123 };
const symbols = object.getownpropertysymbols(obj);
console.log(symbols); // [symbol(id)]
console.log(obj[symbols[0]]); // 123

const obj = { name: 'alice', age: 26 };
const descriptor = object.getownpropertydescriptor(obj, 'name');
console.log(descriptor);
// output: { configurable: true, enumerable: true, value: "alice", writable: true }

console.log(object.is('foo', 'foo')); // true
console.log(object.is({}, {})); // false

const obj = { name: 'Khabib', age: 28 };
const descriptors = Object.getOwnPropertyDescriptors(obj);
console.log(descriptors);
// Output: {
age: {
configurable: true,
enumerable: true,
value: 28,
writable: true },
name: {
  configurable: true,
  enumerable: true,
  value: "Khabib",
  writable: true
 }
}