ES6对象扩展

1属性简写

• 如果对象的属性值是一个变量，且该变量名和该属性名相同，那么，可以简写为如下形式：

let a = 3;
let b = 5;
let obj = {
  a,
  b
}

• 属性方法的简写

let obj = {
  add(a,b){
    return a+b;
  }
}
obj.add(3,5);//8

2 es5中对象的key必须是数值或字符的直接量，es6中属性key可使用变量，如：

let a = 'name';
let obj = {
  [a]:'zhangsan'
}
console.log(obj.name);//zhangsan

3 Object新增api

• Object.is(arg1,arg2),相当于arg1===arg2
  如：

console.log(Object.is('abc','abc'));//true
console.log(Object.is([],[]));//false

• Object.assign(obj1,obj2)，将我obj2浅拷贝至obj1。

let obj1 = {
  name:'zhangsan'
}
let obj2 = {
  age:18
}
console.log(Object.assign(obj1,obj2));//{name: "zhangsan", age: 18}

• let ...of Object.entries(obj)遍历对象

let obj = {
  name:'zhangsan',
  age:18
}
for(let [key,value] of Object.entries(obj)){
    console.log(key+":"+value);
}
//name:'zhangsan'
//age:18

• ...解构赋值
  如：

let obj = {
     name:'zhangsan',
    age:18,
    count:60
}
let {name,...c} = obj;
console.log(c);//{age: 18, count: 60}

ES6总篇--目录