how to add comas to thousands in js code example

Example 1: format money javascript commas

function formatMoney(n) {
    return "$ " + (Math.round(n * 100) / 100).toLocaleString();
}

n = 2123000;
// =>2,123,000

Example 2: javascript format numbers with commas

function numberWithCommas(x) {
    return x.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ",");
}