Update price automatically when quantity changed on product page Magento

Question

I am looking to have the product price automatically updated based on the quantity the customer has chosen.

Currently when you choose a custom option in magento the price automatically updates but when choosing quantity this does not.

So the scenario would be the product price is £10. User enters 3 quantity and automatically on the product page it updates the price to £30 and so on.

Does anybody know of a simple way of updating this?

Answer 1

Using jquery you can do this

$('#qty').keyup(function(){
    if($(this).val() != '' && isNumber($(this).val()) && $(this).val() > 0)
    {
       var price = $('#real_price').val() * 1;
       var qty = $(this).val() * 1;
       var total = price * qty;
       $('#price').html(total);
    }
    else
    {
       $('#price').html('500');    
    }
});

function isNumber(n) {
    return !isNaN(parseFloat(n)) && isFinite(n);
}

FIDDLE

Answer 2

Use jquery::

HTML CODE::

<input type='number' id='quantity'/>
<span id='total_price'></span>

Jquery Code::

var price=100;
$("#quantity").on("change",function(){
    quantity=$(this).val();
    total_price=price*quantity;
    $("#total_price").html(total_price);

})

Answer 3

In Magento 1.9.2.4, the code file to edit is js/varien/product.js

In Magento 1.9.3 and above, the file to edit is js/varien/product_options.js

Add the following code:

var qty;
if($('qty').getValue().length == 0 || isNaN($('qty').getValue()) || $('qty').getValue() <= 0) { 
    qty = 1;
} else { 
    qty = $('qty').getValue();
    price *= qty;
}

right after

if (price < 0) price = 0;

and before

if (price > 0 || this.displayZeroPrice) { ...

And, at the end of the file add:

Event.observe(window, 'load', function() {
    $('qty').observe('blur', function(e){
        optionsPrice.reload();
    });
});

Source: https://magentojai.blogspot.com/2015/06/price-update-while-change-qty-in.html

Answer 4

Add the following script at the end in your template\catalog\product\view.phtml

<script>
$('qty').observe('blur', function(e){
    $('qty').value = Math.max($F('qty').replace(/[^\d].*/, ''), 1);
    optionsPrice.productPrice = Math.max(optionsPrice.productOldPrice, $F('qty') * optionsPrice.productOldPrice);
    optionsPrice.reload();
});
</script>