I have a language center where students top up there cards to visit classes, now I have a button and an input filed of number in the dynamic page. the button has the label "Top Up For 12 Lessons". When I press this button I want to add the sum 12 to the number the filed has. For example. The student has 6classes remaining but he wants to top up the card, I press the button "Top Up For 12 Lessons" and it adds 12 to the number 6. So I get 12+6=18
I don't need the button to save the dataset, I just need to add the sum.
How can I have this work with an onClick event?
Please can someone give me the code for this?
Thanks in advance!