Hi,

I have a form with a field called 'Serial_No'. This is a 9 digit number that
will be in the form NN-NNN-NN. I would like to have a hidden field further
down the page within the same form called 'Category' that will contain the
first 2 characters of the 'Serial_No' field.

I know how to do this by having the hidden field on the next page and use
request.form but I need the hidden field to be on the same form.

Can anyone help?