Trying to grab value from div with req.body

In express app I have button which incrementing value, and that value should be multiple with price. That value is in a div, not in a form. In JS I would do something like this:

document.getElementById('quantity').innerHTML;

But how to grab this value with express? I was thinking with help of hidden form element, has anyone suggestion or better solution?

<td data-th="Quantity" id="quantity" class="text-right">5</td>

<form action="#" method="get">
  <input type="hidden" name="quantityVal" value="">
</form>

img

via perija