I want to destroy the cookie by the php condition but i have not got anything to do that after the lots of research on the google and php manual . i have read at some place that setcookie('cookie_name'); but it just erase the cookie so my question is that how to destroy cookie by php ?
When deleting a cookie you should assure that the expiration date is in the past, to trigger the removal mechanism in your browser
setcookie ("cookie_name", "", time() - 3600); // set the expiration date to one hour ago
Manual.
There is no way to erase a cookie in PHP perse. What setcookie("cookie_name"); does is it instructs the browser to keep the cookie untill now, meaning that it can clean it up (you normally give it a date sometime in the future).
You can not force a cookie to be deleted.
If you need better control over what data is kept in the current session use server-side session storage. Keep only the session_id in the cookie.
Destroying cookies is upto the browser however you can remove a cookie (which is the same for your app) by setting the date in the past:
setcookie($cookie_name, "", 1);
Most set the time to 1970.
Ha! #MikeBrant makes a good point. Since PHP can't understand if setcookie was done to remove a cookie $_COOKIE is still set after issuing this command so you have to unset it.
Related
I've found that if I set a cookie with no expiration value and then create another cookie, the first cookie seems to be destroyed. Is this because a new session is created or is it because it is another request?
I've resolved my 'problem' by actually setting an expiration time, but I'm just curious to know what is actually happening when the second cookie is being created.
setcookie('cookieA', 'stuff', null, '/');
setcookie('cookieB', 'stuff', time() + 1200, '/');
$expire_time has it's own role in function setcookie and if it's less than now the cookie is deleted. There's no way not to set an expiration time or set it to null. It's simply a specification of cookies to achieve an expiration time (http://www.faqs.org/rfcs/rfc2965.html).
If you want the cookie to last forever, just set it to enormously huge number
Good Luck. :)
I am new to php , I came across cookie and persistent cookie and i understand the difference between them.My question is that how can i make cookie persistent or temporary.I found only one syntax for cookies
<?php
setcookie("user", "Alex Porter", time()+3600);
?>
Thanks
Phisically speaking, there is only one kind of cookie. You can make it persistent by choosing a large enough expiration time. If the expiration time is set to 0, the cookie will last only until your page is opened in the browser.
Your example cookie is persistent, it expires in one hour.
Here is a link with a short explanation.
Most likely you can hardly access the phisical cookie on your hard disk, because borwsers store them in their internal logic. For example Firefox store cookies in a local SQLite database file in the browser's profile folder.
When creating a cookie, 3rd argument (time()+3600 in your example) specifies cookie's expiry date.
time()+3600 means now+3600 seconds, which is 1 hour in the future. Time() function returns current time (unix time) in seconds.
There is no such thing as a really permanent cookie, more like expiring far in the future cookie.
I have heard many times that a session get destroy as our browser close.
Then how I keep logged in after closing and reopening my browser.
Please help
You keep login because your sessions are not destroyed even when the browser is closed. Sessions destroying on the closing of the browser is default behaviour but but this does not mean its the only behaviour. You can extend the expiry time of session.
This behaviour can be changed in the php.ini file by altering the line:
Keeping a session alive indefinitely
session.cookie_lifetime = 0
So just check when you have set the expiry time for the sessions. Although using cookies will be a good option
Note:- Remember to restart your web server after making this change.
You have to use Cookies.
You can use the setcookie() function and read the value with the $_COOKIE['cookiename'] variable.
Use cookies, with a predefined expire time, I like 1 year
You can use cookies. Cookies are data that is stored directly on the HDD so that even if the browser was closed, cookies still can be read if it haven't expired yet.
Here is an example of setting up a cookie.
Paste this code BEFORE the tag.
<?php setcookie("$name", "$value", $time); ?>
Where $name is the cookie name, $value is the cookie value and $time is the time when your cookie will be expired. For example $time = time()+86400; will set your cookie to expire after 1 day. The 86400 value is the number of seconds in a day, 60seconds times 60minutes times 24hours, so 60x60x24 = 86400.
How to delete session cookie on browser close, or optionally detect and force "new" session for a returning user. I want to prevent storing session cookies by "session managers" like addons in firefox and such.
I guess you could use this :
session_set_cookie_params(0);
session_start();
Destroy PHP Session on closing
Session manager are designed to save session cookie : I don't think you can prevent their behavior.
However, you can set your php configuration to have a non-used session garbage collected really fast : Then the session, after a few amount of time (basically, 1 hour), will be invalidate. See the session.gc_maxlifetime parameter.
fortunately a website can't force anything to happen on the clients machine. if you don't want to rely on the browsers cookie-management and those addons, one way would be to not use cookies for sessions and use the good old session-id get parameter instread (or, alternatively, set the session-lifetime to something like 1 or 2 hours, but this isn't exactly what you wanted)
I don't think you'll be successful on this route.
If you need to log out the user so quickly, consider using a very short session lifetime (like, one minute) and keeping the session alive using a JavaScript setInterval or an iframe that refreshes itself every thirty seconds.
Does the $_SESSION expire at any time point? Obviously you can call session_destroy() or close the browser. I just had a application fail because it was relying on the session and the browser had been open for 2 days. I guess the session must have expired.
Yes it can be configured in the php.ini. See here http://www.php.net/manual/en/function.session-cache-expire.php
I think one way is to set http://www.php.net/manual/en/session.configuration.php#ini.session.cookie-lifetime , but then you rely on the browser to really delete the session cookie when it expires. So it would be best to save the last-seen-time in the session and remove sessions when a maximum time is reached.