Detect whether the browser is refreshed or not using PHP

Question

I want to detect whether the browser is refreshed or not using PHP, and if the browser is refreshed, what particular PHP code should execute.

Answer 1

 1)
    {
        echo "You hit the refresh button!";
    }
    else
    {
        echo "This is my site";
    }

    // To clear out the visits session var:
    // unset($_SESSION["visits"]);

?>