Sessiondestroy,sessionstart.In PHP manual, the description for sessiondestroy function is:sessiondestroy destroys all of the data associated with the current session. It does not unset any of the global variablePixelstech, this page is to provide vistors information of the most updated technology information around the world. And also, it will provide many useful tips on our further. A PHP session can be destroyed by sessiondestroy function. This function does not need any argument and a single call can destroy all the session variables. If you want to destroy a single session variable then you can use unset function to unset a session variable. Here is the example to unset a single variable −.

A session lasts until your visitor closes their browser - if they navigate away to another page, then return to your site without having closed their browser, their session will still exist . This behaviour is usually desirable - potentially your visitor's session data might last for days, as long as they keep browsing around your site, whereas cookies usually have a fixed lifespan.

If you want to explicitly end a user's and delete their data without them having to close their browser, you need to clear the $_SESSION array, then use the session_destroy() function. Msvc 2015 download. Session_destroy() removes all session data stored on your hard disk, leaving you with a clean slate.

To end a session and clear up its data, use this code:

There are two important things to note there: firstly, session_start() is called so that PHP loads the user's session, and secondly we use an empty call to the array() function to make $_SESSION an empty array - effectively wiping it. If session_start() is not called, neither of the following two lines will work properly, so, again, always call session_start()!

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Sessiondestroy; to destroy the session. But what I would like to do is destroy the session after 2 hours have been passed. Any idea on how to do it and also where should I put it? I have something like this. Session library in Codeigniter 4 Create and destroy session ci4 session.

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In this tutorial you will learn how to store certain data on the server on a temporary basis using PHP session.

What is a Session

Although you can store data using cookies but it has some security issues. Since cookies are stored on user's computer it is possible for an attacker to easily modify a cookie content to insert potentially harmful data in your application that might break your application.

Also every time the browser requests a URL to the server, all the cookie data for a website is automatically sent to the server within the request. It means if you have stored 5 cookies on user's system, each having 4KB in size, the browser needs to upload 20KB of data each time the user views a page, which can affect your site's performance.

You can solve both of these issues by using the PHP session. A PHP session stores data on the server rather than user's computer. In a session based environment, every user is identified through a unique number called session identifier or SID. This unique session ID is used to link each user with their own information on the server like emails, posts, etc.

Tip: The session IDs are randomly generated by the PHP engine which is almost impossible to guess. Furthermore, because the session data is stored on the server, it doesn't have to be sent with every browser request.

Session Destroy Php


Starting a PHP Session

Before you can store any information in session variables, you must first start up the session. To begin a new session, simply call the PHP session_start() function. It will create a new session and generate a unique session ID for the user.

The PHP code in the example below simply starts a new session.

The session_start() function first checks to see if a session already exists by looking for the presence of a session ID. If it finds one, i.e. if the session is already started, it sets up the session variables and if doesn't, it starts a new session by creating a new session ID.

Note: You must call the session_start() function at the beginning of the page i.e. before any output generated by your script in the browser, much like you do while setting the cookies with setcookie() function.

Storing and Accessing Session Data

You can store all your session data as key-value pairs in the $_SESSION[] superglobal array. The stored data can be accessed during lifetime of a session. Consider the following script, which creates a new session and registers two session variables.

To access the session data we set on our previous example from any other page on the same web domain — simply recreate the session by calling session_start() and then pass the corresponding key to the $_SESSION associative array.

Session_destroy php

Destroy Session Php

The PHP code in the example above produce the following output.

Hi, Peter Parker

Note: To access the session data in the same page there is no need to recreate the session since it has been already started on the top of the page.

Destroying a Session


If you want to remove certain session data, simply unset the corresponding key of the $_SESSION associative array, as shown in the following example:

However, to destroy a session completely, simply call the session_destroy() function. This function does not need any argument and a single call destroys all the session data.

Php Destroy Session Variable

Note: Before destroying a session with the session_destroy() function, you need to first recreate the session environment if it is not already there using the session_start() function, so that there is something to destroy.

Unset Session

Every PHP session has a timeout value — a duration, measured in seconds — which determines how long a session should remain alive in the absence of any user activity. You can adjust this timeout duration by changing the value of session.gc_maxlifetime variable in the PHP configuration file (php.ini).