slice,splice的区别和使用

let arrOne = [22,33,44,55,66];
let arrTwo = arrOne.slice(1,3);//参数是根据数组的下标来截取的
console.log(arrTwo); //[33,44]
console.log(arrOne);//[22,33,44,55,66]

let arrThree = [11,23,34,44,56,67,88,99]
let arrFour = arrThree.splice(2,3) //删除第三个元素以后的三个数组元素(包含第三个元素)
console.log(arrFour);//[33,44,56],删除的元素
console.log(arrThree);//[ 11, 23, 67, 88, 99 ]//原数组中已经没有删除后的三个元素了
let arrFive = arrThree.splice(2,0,'望','奶奶','平安')
//从第2位开始删除0个元素，插入"望","奶奶",'平安'
console.log(arrFive);//返回一个空数组[]
console.log(arrThree);//[ 11, 23, "望", "奶奶", "平安", 67, 88, 99 ]
var arrSix = arrThree.splice(2,3,"平平","安安");
//从第2位开始删除3个元素，插入"平平","安安"
console.log(arrSix); //[ "望", "奶奶", "平安" ]
console.log(arrThree); //[ 11, 23, "平平", "安安", 67, 88, 99 ]
var arrSeven = arrThree.splice(2);//从第三个元素开始删除所有的元素
console.log(arrSeven);//[ "平平", "安安", 67, 88, 99 ]
console.log(arrThree); //[11, 23]