[SOLVED] Order form grand total

[Kano]

Hi there,

Can someone help me please.

 

I have an order form in which PHP freaks kindly helped me build a while back, but I am having problems with including a grand total to the form.

 

Each line of the form has a sub-total which javascript works out by * the qty (select tag) with the price, the javascript is 'onchange' on the select tag.

 

Now i want the forms grand total input box to = all the sub-total input boxes.

 

Would this be done within the same javascript function on the select tags (i.e every time there is a change work out grand total)?

 

The sub-totals have a name="subtotal_$wsi_id" (i.e. sub-totals have an index of subtotal_)

 

The grand-total has a name="grandtotal"

 

Many thanks.