Hi,
Please take a look at my form (it will be easier to understand my problem)
When you select 'AMEX' in the dropdown menu 'cardtype', I would like a 3.5% processing fee to be added to the subtotal and shown in the 'processingfee' text field.
I did find the following script that shows 3.5% of subtotal. I pasted it in the 'processingfee' text field.
var f = this.getField("subtotal");
event.value = Math.round(f.value * 3.5) / 100;
but I need this to work ONLY when 'AMEX' is selected in the 'cardtype dropdown menu'. All other items in the dropdown menu should return 0.
How can I achieve this?
Thank you in advance!