我如何在PHP中注销？

<?php
    session_start();
    session_destroy();
    if(isset($_COOKIE['cookemail_id']) && isset($_COOKIE['cookpassword']))
    {
    setcookie("cookemail_id", "", time()-60*60*24*100, "/");
    setcookie("cookpassword", "", time()-60*60*24*100, "/");
    setcookie("cooktype", "", time()-60*60*24*100, "/");
    }

?>

Above is my code for log out . But session variable is not getting deleted.

<?php
session_start();
if (isset($_COOKIE['cookemail_id']) && isset($_COOKIE['cookpassword'])) {
    setcookie("cookemail_id", "", time()-42000, "/");
    setcookie("cookpassword", "", time()-42000, "/");
    setcookie("cooktype", "", time()-42000, "/");
}

$_SESSION = array();

if (ini_get("session.use_cookies")) {
    setcookie(session_name(), '', time() - 42000, '/');
}

session_destroy();
?>

The example is right there on the page http://php.net/manual/en/function.session-destroy.php

Put session_destroy(); after the if statement. You don't want to destroy your session right after creating it...

EDIT: Your code is confusing. What session variable are you talking about? I don't see any.

setcookie ("TestCookie", "", time() - 3600);

see php.net/manual/en/function.setcookie.php

Example #2 setcookie() delete example