how to convert this code substr in php to javascript-CodePudding

how to convert this code substr in php to javascript? this code run in php, but run in java script cannot

PHP

<?php
    $header='XII-40';
    $next=1022;
    $len=6;
    $id = $header.substr("000000000$next", -$len);
print   $id;

const str = 'XII-14';
const next=123
const text1='00000000001' next
const len =6
console.log(text1.substr(next, len));

CodePudding user response：

This seems to work:

const str = 'XII-14';
const next = 123;
const text1 = '00000000001'   next;
const len = 6;
console.log(str   text1.substr(-len));

It returns:

XII-14001123