JSFiddle - React, Tailwind, and code Playground

HTML

<button>
toLocaleString with currency options
</button>

JavaScript

document.querySelector('button').addEventListener('click', function() {
    var num = 3500.99;
    num = num.toLocaleString('de-DE', {
       style: 'currency',
       currency: 'ZAR',
       currencyDisplay: 'symbol',
       useGrouping: true
    });
    alert(num);
}, false);