...放在参数中 为 Rest 参数 的意思就是不确定传几个参数
1
<script type="text/javascript">
function zs(...m){ Rest 参数
let totle=0;
for(var i of m){
totle+=i
}
console.log(totle)
}
zs(4,5,6)
</script>
箭头函数
<script type="text/javascript">
let totle=0;
let zs=(...m)=>{
for(var i of m){
totle+=i
}
console.log(totle)
}
zs(12,1)
</script>
2 数组元素的合并
<script type="text/javascript">
let arr1=[1,2,3]
let arr2=[4,5,6]
console.log([...arr1,...arr2]) 结果[1,2,3,4,5,6]
</script>
<script type="text/javascript">
let [x,...y]=[1,2,3,4]
console.log(y) 结果[2, 3, 4]
</script>
<script type="text/javascript">
let [a,b,c]="es6"
console.log([a,b,c]) 结果[e, s, 6]
</script>
<script type="text/javascript">
let b =[...'es6']
console.log(b) 结果[e, s, 6]
</script>