function checkQuantity(numContracts) {
  for (i = 1; i <= numContracts; i++) {
    var quantityInput = document.getElementById("quantity" + i);
    if (quantityInput) {
      var productQuantity = parseInt(quantityInput.value);
      if (productQuantity > 0)
        return true;
    }
  }

  alert("Please fill the Quantity box of at least one item");
  return false;
}

function addQuantity(numFieldId) {
  var quantityInput = document.getElementById("quantity" + numFieldId);
  if (quantityInput) {
    var Quantity = parseInt(quantityInput.value);
    if (isNaN(Quantity)) 
      quantityInput.value = 1;
    else
      quantityInput.value = Quantity + 1;
    return true;
  }
  else
    return false;
}

function intOnly(Field) {
  if (Field.value != '')
    if (/[^\d]/g.test(Field.value))
      Field.value = Field.value.replace(/[^\d]/g, '');
}