var changedQ = false;
function checkQ() {
  if (changedQ) {
     if (confirm("You have changed a quantity without clicking 'Make Changes'. If you leave now you will " +
                 "not save this new quantity. Do you wish to leave?")) {
        location.href = '/Shop_Items/';
     }
  } else {
    loadurl("/Shop_Items/");
  }
}

function loadurl(url) {
  location.href = url;
} 

function checkValue(x, obj) {
  if (x == 0) {
     alert("This item will be erased from your basket.");
     document.basket.submit();
  }
  else if (x.indexOf(".") != -1) {
     alert("Quantities can only be whole numbers.");
     obj.focus();
     obj.select();
     return(false);
  }
  else if (isNaN(x) || x < 0) {
     alert("Please enter a valid quantity.");
     obj.focus();
     obj.select();
     return(false);
  }
  return(true);
}