push加入到数组最后面
let arr1=[1,2,3]
let arr2=arr1.push(4)
//arr2=[1,2,3,4]
unshift加入到数组最前面
let arr1=[2,3,4]
let arr2=arr1.unshift(1)
//arr2=[1,2,3,4]
pop 删除数组最后一个 shift删除第一个
let arr=[1,2,3,4,5,6]
let arr1=arr.pop()
//arr1=[1,2,3,4,5]
let arr2=arr1.shift()
//arr2=[2,3,4,5]
splice(下标,数量)删除指定数组的个数位置
let arr1=arr.splice(1,2)
//arr1=[1,4,5,6]
数组的链接concat
let arr1=[1,2,3]
let arr2=[4,5,6]
let arr3=arr1.concat(arr2)
//arr3=[1,2,3,4,5,6]
方法二
let arr4=arr1.push(...arr2)
//arr4=[1,2,3,4,5,6]
