Object Skill

对象相关的JS技巧。

克隆对象

const _obj = {a: 0, b: 1, c: 2}; // 以下方法任选一种
const obj = {..._obj};
const obj = JSON.parse(JSON.stringify(_obj));
// obj => {a: 0, b: 1, c: 2}

合并对象

const obj1 = {a: 0, b: 1, c: 2};
const obj2 = {c: 3, d: 4, e: 5};
const obj = {...obj1, ...obj2};
// obj => {a: 0, b: 1, c: 3, d: 4, e: 5}

对象字面量

获取环境变量时用此方法，很舒服

const env = 'prod';
const link = {
    dev: 'Development Address',
    test: 'Testing Address',
    prod: 'Production Address'
}[env];
// link => 'Production Address'

对象变量属性

const flag = false;
const obj = {
    a: 0,
    b: 1,
    [flag ? 'c' : 'd'] : 2
};
// obj => {a: 0, b: 1, d: 2}

创建纯空对象

const obj = Object.create(null);
Object.prototype.a = 0;
// obj = {}

删除对象无用属性

const obj = {a: 0, b: 1, c: 2}; // 只想拿b和c
const {a, ...rest} = obj;
// rest => {b: 1, c: 2}

解构对象属性嵌套

const obj = {a: 0, b: 1, c: {d: 2, e: 3}};
const {c: {d, e}} = obj;
// d e => 2 3

解构对象属性别名

const obj = {a: 0, b: 1, c: 2};
const {a, b: d, c: e} = obj;
// a d e => 0 1 2