Backend DevelopmentPHP TutorialImplement the session and cookie data value transfer function in PHPImplement the session and cookie data value transfer function in PHP
1.session After logging in to the previous page, if there is no operation for a long time, you need to log in again after refreshing the page.
Features: (1) The session is stored on the server;
(2) Each person (login) saves a copy of the session;
(3) The session has a default Expiration time; (If too many people log in, there will be too much data. Since it is stored on the server, it will put pressure on the server and will be cleared after a certain period of time)
(4) Any arbitrary data can be stored in the session type of data.
From the above characteristics, it can be concluded that the characteristics of session are relatively safety. The disadvantage is that it puts a certain amount of pressure on the server.
(5) When a page needs to use session, you need to add session_start() at the top of the page; it should be written at the top of the page, and no code can appear in front. The code refers to the PHP code, which can be There is HTML code. It is best to develop a habit and write at the top of the page. Just write one page once.
(6) Manipulate session. a. Assignment. b. Value.
Assignment:
<?php
session_start();//session开始标签，在最顶部写。?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<body>
<?php
$_SESSION["uid"] = "zhangsan";//给$_SESSION["uid"]赋值。?>
</body>
</html>Value:
The value can be obtained on any page, for example, when making a login page, you can Assign the login name, password name and other information to $_SESSION["uid"]. You can also get the login name, password name and other values from other pages on the same browser, provided that the assigned page has been opened first. If you directly open other pages to get the value, you will not be able to get it. Then, if you close the browser and then open it again, you must first open the assignment page before other pages can get the value.
<?php
session_start();?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<body>
<?php
echo $_SESSION["uid"]?>
</body>
</html>2. Cookie
Features: (1) Cookies are stored on the client side, and the browser will have a cookie clearing option when clearing browsing information.
(2) Save one cookie per person.
(3) There is no default expiration time for cookies.
(4) Only strings can be stored.
From the above characteristics, it can be concluded that cookies are not safe and will not put pressure on the server.
If there are no special requirements, both session and cookie can be used, but when it comes to higher security, session should be selected.
The above is the detailed content of Implement the session and cookie data value transfer function in PHP. For more information, please follow other related articles on the PHP Chinese website!
Explain the concept of a PHP session in simple terms.Apr 26, 2025 am 12:09 AMPHPsessionstrackuserdataacrossmultiplepagerequestsusingauniqueIDstoredinacookie.Here'showtomanagethemeffectively:1)Startasessionwithsession_start()andstoredatain$_SESSION.2)RegeneratethesessionIDafterloginwithsession_regenerate_id(true)topreventsessi
How do you loop through all the values stored in a PHP session?Apr 26, 2025 am 12:06 AMIn PHP, iterating through session data can be achieved through the following steps: 1. Start the session using session_start(). 2. Iterate through foreach loop through all key-value pairs in the $_SESSION array. 3. When processing complex data structures, use is_array() or is_object() functions and use print_r() to output detailed information. 4. When optimizing traversal, paging can be used to avoid processing large amounts of data at one time. This will help you manage and use PHP session data more efficiently in your actual project.
Explain how to use sessions for user authentication.Apr 26, 2025 am 12:04 AMThe session realizes user authentication through the server-side state management mechanism. 1) Session creation and generation of unique IDs, 2) IDs are passed through cookies, 3) Server stores and accesses session data through IDs, 4) User authentication and status management are realized, improving application security and user experience.
Give an example of how to store a user's name in a PHP session.Apr 26, 2025 am 12:03 AMTostoreauser'snameinaPHPsession,startthesessionwithsession_start(),thenassignthenameto$_SESSION['username'].1)Usesession_start()toinitializethesession.2)Assigntheuser'snameto$_SESSION['username'].Thisallowsyoutoaccessthenameacrossmultiplepages,enhanc
What are some common problems that can cause PHP sessions to fail?Apr 25, 2025 am 12:16 AMReasons for PHPSession failure include configuration errors, cookie issues, and session expiration. 1. Configuration error: Check and set the correct session.save_path. 2.Cookie problem: Make sure the cookie is set correctly. 3.Session expires: Adjust session.gc_maxlifetime value to extend session time.
How do you debug session-related issues in PHP?Apr 25, 2025 am 12:12 AMMethods to debug session problems in PHP include: 1. Check whether the session is started correctly; 2. Verify the delivery of the session ID; 3. Check the storage and reading of session data; 4. Check the server configuration. By outputting session ID and data, viewing session file content, etc., you can effectively diagnose and solve session-related problems.
What happens if session_start() is called multiple times?Apr 25, 2025 am 12:06 AMMultiple calls to session_start() will result in warning messages and possible data overwrites. 1) PHP will issue a warning, prompting that the session has been started. 2) It may cause unexpected overwriting of session data. 3) Use session_status() to check the session status to avoid repeated calls.
How do you configure the session lifetime in PHP?Apr 25, 2025 am 12:05 AMConfiguring the session lifecycle in PHP can be achieved by setting session.gc_maxlifetime and session.cookie_lifetime. 1) session.gc_maxlifetime controls the survival time of server-side session data, 2) session.cookie_lifetime controls the life cycle of client cookies. When set to 0, the cookie expires when the browser is closed.
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.
Atom editor mac version download
The most popular open source editor
VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft
SublimeText3 Linux new version
SublimeText3 Linux latest version
DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software
