let fruits = ['"htmlcode">

let fruits = ['"htmlcode">

let user = {name : "John", age : 20 }
let userCopy = {...user}


延展操作运算符不执行深度复制。
3.延展操作运算符合并


let fruits = ['"htmlcode">

let user1 = {name : "John", age : 20 };
let user2 = {name : "Ram", salary: '20K' };
let userCopy = {...user1, ...user2};
userCopy ; // {name : "Ram", age :20 , salary : '20K'};


4.延展操作运算符作为参数传递


function sum(a, b) {
 return a+b;
}
let num = [1,2];
sum(...num); // 3


与 math 函数一起使用


let num = [5,9,3,5,7];
Math.min(...num);
Math.max(...num);


5.延展操作运算符在解构变量中




let [melon, ...fruits ] = ['"htmlcode">

let user = {name : "Ram", age: 20, salary: '20K', job : "Tester" };
let { name, age, ...details } = user;
name; // Ram
age; // 20
details; // {salary: '20K', job : 'Tester'};


6.将NodeList对象转换为数组
NodeList类似于数组，但是没有 Array 的所有方法，例如 forEach，map，filter 等。


let nodeList = document.querySelectorAll('.class')
var nodeArray = [...nodeList]


7.将字符串转换为字符
字符串也是可迭代的对象，因此我们也可以使用 ... 来字符串。


let name = "Ram";
let chars = [...name]; // ["R", "a", "m"]



8.从数组中删除重复项


let num = [1, 3, 1, 3, 3, 1];
let uniqueNum = [...new Set(num)];
uniqueNum; //[ 1, 3 ]


总结

                                
                                

                                    javascript中的运算符,js,spread运算符,js运算符有哪些 
                                

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