How do I stop the Back and Refresh buttons from resubmitting my form?

Question

I am doing web development.

I have a page to do with credit card, which when user click \"refresh\" or \"Back\", the transaction will be performed one more time, wh

Answer 1

1. generate a random string and store it in session,

2. then output it to your form as a hidden value,

3. check the submitted and store variable, if matches process your request,

4. go to 1.