<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>Document</title>
</head>
<body>
<script type="text/javascript" >
let arr1 = [1,3,5,7,9]
let arr2 = [2,4,6,8,10]
console.log(...arr1); //展开一个数组
let arr3 = [...arr1,...arr2]//连接数组
//在函数中使用
function sum(...numbers){
return numbers.reduce((preValue,currentValue)=>{
return preValue + currentValue
})
}
console.log(sum(1,2,3,4));
//构造字面量对象时使用展开语法
let person = {name:'tom',age:18}
let person2 = {...person}
//console.log(...person); //报错,展开运算符不能展开对象
person.name = 'jerry'
console.log(person2);
console.log(person);
//合并
let person3 = {...person,name:'jack',address:"地球"}
console.log(person3);
</script>
</body>
</html>