What are the ways to prevent users to take screenshot of a webpage? [duplicate]

Question

Possible Duplicate:
How do i prevent from printscreen of my webpage?

I want to prevent users from taking screen shots of a web-page. What should be the code I have to place in that .html file?

What should be the code to prevent button press like print screen? Because many website prevents users from pressing any keys.

Answer 1

Screenshots are not controlled by the web browser, they are controlled by software running on the user's operating system and cannot be remotely controlled by a web server.

Answer 2

It is possible. Try this css feature.

html {
    display: none;  /* hide whole page - the only true way to prevent screenshots */
}