Prevent PHP script from being flooded

Question

I want to prevent my script, from being flooded - if user hit F5 it is executing the script every time.

I want to prevent from this and allow one script execution pe

Answer 1

1. Store the last execution time of your script in a database or a file.
2. Read from that file/database and compare to the current time.
3. If the difference is under 2 seconds, terminate the script.
4. Else, continue normally.