Question

I have a PayPal button with a quantity text field. How could I check to ensure this textfeild is > 0 so that it does not add to cart if quantity is not an integer >= 1?

Answer 1

Paypal carts are smart enough not to count negative orders. But you could also provide some javascript logic to your client-side that would prevent the action from taking place if the value is less than 1.

A bit of Javascript/jQuery as an example:

$("submit").click(function(e){
  var qty = $(this).closest("form").find("[name='qty']").val();
  if (qty < 1) {
    e.preventDefault();
  }
});