How to disable back button in browser

Answer 1

only reasons that comes to my mind are nefarious. but yes, why would one want to do that?

Answer 2

I don't think you can, also why would you do that?

Answer 3

i need to generate one payment id for one transaction

Answer 4

Do what all other systems do for that, state that using back might cause double charges and don't worry about it. You don't have that kind of access to the browser. It might lead to hacking the browser or user so they don't support anything like that.