session_cache_expire
(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)
session_cache_expire — 返回/设置当前缓存的到期时间
说明
session_cache_expire() 返回
session.cache_expire 的设定值。
请求开始的时候，缓存到期时间会被重置为 180，并且保存在 session.cache_expire 配置项中。 因此，针对每个请求，需要在 session_start() 函数调用之前 调用 session_cache_expire() 来设置缓存到期时间。
参数
value-
如果指定
value且不为null，就使用value的值替换当前缓存到期时间。注意: 仅在
session.cache_limiter的设置值 不是nocache的时候， 才可以设置value参数。
返回值
返回 session.cache_expire 的当前设置值，
以分钟为单位，默认值是 180 （分钟）。如果更改值失败，则返回 false。
更新日志
| 版本 | 说明 |
|---|---|
| 8.0.0 |
value 现在可以为 null。
|
示例
示例 #1 session_cache_expire() 示例
<?php
/* 设置缓存限制为 “private” */
session_cache_limiter('private');
$cache_limiter = session_cache_limiter();
/* 设置缓存过期时间为 30 分钟 */
session_cache_expire(30);
$cache_expire = session_cache_expire();
/* 开始会话 */
session_start();
echo "The cache limiter is now set to $cache_limiter<br />";
echo "The cached session pages expire after $cache_expire minutes";
?>
＋添加备注
用户贡献的备注 2 notes
Anonymous ¶
17 years ago
The manual probably doesn't stress this enough:
** This has nothing to do with lifetime of a session **
Whatever you set this setting to, it won't change how long sessions live on your server.
This only changes HTTP cache expiration time (Expires: and Cache-Control: max-age headers), which advise browser for how long it can keep pages cached in user's cache without having to reload them from the server.
tuncdan dot ozdemir dot peng at gmail dot com ¶
1 year ago
Using PHP 8.2
session_start();
$result1 = session_cache_expire( 30 ); // setter, results in Warning: Session cache expiration cannot be changed when a session is active in ...
$result2 = session_cache_expire(); // getter
var_dump( $result1, $result2 ); // prints out: int(180) int(180) [note: 180 is the default value]
Because the session was already started, cache expiration could not be changed (warning message). However, the return value is NOT false, it is still the original, unchanged value!
So I do not know what is considered a failure to change the value as per the documentation (`On failure to change the value, false is returned.`).备份地址：http://www.lvesu.com/blog/php/function.session-cache-expire.php