Multiple parameters?!?!

I’m trying to make a javescript which get the parameter from a selectfield like this:

function UpdateQty(item)
{
   product_id = item.name;
   newQty = item.options[item.selectedIndex].text;
   document.location.href = 'index.php?page=update&product_id='+product_id+'&action=update_product';
}

And it is getting the data from a selectfield like this:

<select name=1 onchange="UpdateQty(this);">
   <option value=1>1</option>
   <option value=2>2</option>
   <option value=3>3</option>
</select>
<select name=2 onchange="UpdateQty(this);">
   <option value=1>1</option>
   <option value=2>2</option>
   <option value=3>3</option>
</select>
<select name=3 onchange="UpdateQty(this);">
   <option value=1>1</option>
   <option value=2>2</option>
   <option value=3>3</option>
</select>

This works just fine, but now I want to put an ekstra parameter into the updateurl like this:
document.location.href = ‘index.php?page=update&product_id=’+product_id+‘&color_id=‘+color_id+’&action=update_product’;

I want to do so with an hidden field for each selectbox… How do I do So!!!

Thanks in advance :slight_smile: