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HomeBackend DevelopmentPHP Tutorialsession_destroy()不能立即生效

在html里用链接到一个php页面,该php页面会销毁session,但是当打开该页面的时候session还存在,只有再刷新一次该php页面才能销毁session。该页面就两条语句$_SESSION = array();session_destroy();     session_start()已经开启。
请问这是什么情况


回复讨论(解决方案)

你在 B页面中执行 session_destroy(); 前 session 自然是存在的,否则就没必要 session_destroy(); 了
你只在重入B页面(比如刷新)才会发现 session 没有了
因为对用户而言, session_destroy() 只是发送注销 cookie 中的 sessionid 的指令 

a.php

<?phpsession_start();$_SESSION['name'] = "kobe";?><a href="se2.php">se2</a>


b.php
<?phpsession_start();$_SESSION = array();session_destroy();var_dump($_SESSION['name']);?>

A页面跳转到B页面销毁session,同时B页面再跳转到登陆页面,这时候session依然在,是这样的情况

先访问a.php -> b.php -> login.php  session消失。
a.php

<?phpsession_start();$_SESSION['name'] = 'fdipzone';?><a href="b.php">go b</a>

b.php
<?phpsession_start();session_destroy();?><a href="login.php">go login</a>

login.php
<?phpsession_start();echo 'name='.$_SESSION['name'];?>

我找到原因不是destroy的问题。是当用户登录后,会有一个php页面执行一个死循环,在这个循环里每隔30秒更新一次用户的登陆时间,直到用户离开当前页面。

while(true) {	echo "\n";	ob_flush();	flush();		if(connection_aborted()) exit;        /*这里是将当前时间写入到数据库*/	sleep(30);}



如果删除了这里的ob_flush();flush();会解决问题,但是这样的话connnection_aborted()会不生效,用户关闭页面后时间仍然会继续更新。但如果加上了那两句,会发生session无法destroy,必须手动f5后才能删除

请问这样怎么解决?

?甚?要???死循?呢?

?甚?要???死循?呢?


定时向数据库更新登陆时间,如果用户一直在线则一直执行,直到用户关闭页面

那这样页面其实一直都没有结束,当然当前的session就不会消失了。

那这样页面其实一直都没有结束,当然当前的session就不会消失了。


connection_aborted()这一句可以检查客户端是否断开,但是它执行需要在页面输出内容,所以添加了ob_flush();flush();
问题是这两句会导致销毁session的那个页面无法正常执行,也就是必须手动刷新才能销毁session


所以,有没有其他办法,在客户端断开时关闭这个循环。或者有没有其他办法,正常执行销毁session的那个页面。
出现这样的问题是ob_flush();flush();的问题吗?要怎么办呢?

我这么做就是为了防止用户长时间不登陆被踢下线的保活,还有其他办法吗?


那这样页面其实一直都没有结束,当然当前的session就不会消失了。


connection_aborted()这一句可以检查客户端是否断开,但是它执行需要在页面输出内容,所以添加了ob_flush();flush();
问题是这两句会导致销毁session的那个页面无法正常执行,也就是必须手动刷新才能销毁session


所以,有没有其他办法,在客户端断开时关闭这个循环。或者有没有其他办法,正常执行销毁session的那个页面。
出现这样的问题是ob_flush();flush();的问题吗?要怎么办呢?

我这么做就是为了防止用户长时间不登陆被踢下线的保活,还有其他办法吗?

你的页面一直未结束,当前页面的session一直未更新到文件。这就是session_destroy()不能立即生效的原因。
在session_destroy(); 后面加 session_write_close(); 就可以解决这个问题了。



那这样页面其实一直都没有结束,当然当前的session就不会消失了。


connection_aborted()这一句可以检查客户端是否断开,但是它执行需要在页面输出内容,所以添加了ob_flush();flush();
问题是这两句会导致销毁session的那个页面无法正常执行,也就是必须手动刷新才能销毁session


所以,有没有其他办法,在客户端断开时关闭这个循环。或者有没有其他办法,正常执行销毁session的那个页面。
出现这样的问题是ob_flush();flush();的问题吗?要怎么办呢?

我这么做就是为了防止用户长时间不登陆被踢下线的保活,还有其他办法吗?

你的页面一直未结束,当前页面的session一直未更新到文件。这就是session_destroy()不能立即生效的原因。
在session_destroy(); 后面加 session_write_close(); 就可以解决这个问题了。

好的,谢谢~ 没问题了
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