js字符串转数组方法哪些,js字符串转数字数组

//字符串转数组        let str1="123,4,8"        let newarr=str1.split(",")        console.log(newarr)        //数组转字符串        let result=newarr.join(",")        console.log(result)        //字符串截取        console.log(str1.substring(1,3))