es6解构赋值

Posted 2021-02-06 yiquan

• 按照一定的模式从数组和对象中提取值，然后对变量进行赋值，这就是解构赋值

//常见的赋值
let arr = [1,2,3];
let a = arr[0];
let b = arr[1];
let c = arr[2];

//解构的时候，等号的二边结构类似。右边还必须是一个真实的值
let [a,b,c] = arr;
console.log(a,b,c);

let arr2 = [{name:‘zfpx‘,age:9},[1,2],3];
let [{name,age},[d,e],f] = arr2;
let [json,arr3,f] = arr2;
console.log(json,arr3,f);

let obj1 = {name:‘zfpx‘,age:9};
let {name:myname,age:myage} = obj1;
let myname = obj1.name;
let myage = obj1.age;
console.log(myname,myage);

//默认解构，如果能取出来值就用取出来的值，如果取不出来就用默认值
let obj2 = {name:‘zfpx‘,age:9};
let {name,age=8} = obj2;
console.log(name,age);

let arr4 = [1,2,3];
//省略赋值
let [,,j] = arr4;
console.log(j);

• 更多参考：阮一峰es6