PHP防止频繁刷新

PHP防止频繁刷新

<?php
session_start();
$hackhp = "3";
if (isset($_SESSION["hackhp"])) {
    if (time() - $_SESSION["hackhp"] < $hackhp) {
        exit("请不要频繁刷新，休息3秒再刷新吧");
    } else {
        $_SESSION["hackhp"] = time();
    }
} else {
    $_SESSION["hackhp"] = time();
}
?>