What is PHP object-oriented and the three major characteristics of object-oriented-PHP Tutorial-php.cn

Home

Backend Development

PHP Tutorial

What is PHP object-oriented and the three major characteristics of object-oriented

巴扎黑

Jan 09, 2018 pm 01:09 PM

What is object-oriented?

Object-oriented programming, which we often call OOP, is actually part of object-oriented programming. There are three parts to object-oriented: object-oriented analysis (OOA), object-oriented design (OOD), and object-oriented programming (OOP). What we are going to learn now is object-oriented programming, and the two first and most important concepts to understand in object-oriented programming are classes and objects.

Classes and Objects

Everything is an object. We can regard everything in the world as an object, because they all have their own attributes. For example: people have attributes such as height, weight, age, gender, etc., and they can also sing, dance, run and other behaviors. If people are regarded as a class, then height, weight, age, and gender are the attributes of the human class, and singing, dancing, and running are the behaviors of the human class.

You can try to look at the things around you. We can all regard it as a class. Give more examples to deepen your understanding of the concepts of classes and objects.

When we try to give examples, we are invisibly instantiating classes. For information on instantiating classes, please see: Definition and instantiation methods of php classes

Three major characteristics of object-oriented programming

(1). Encapsulation

The simple explanation is to put the function in a box , when you want to use this function, open the box, take it out and use it.

(2). Inheritance

Subclasses automatically inherit the properties and methods in one or more parent classes, and can override or add new properties or methods.

This feature simplifies the creation of classes and objects and improves code reusability.

(3).Polymorphism

means that a class can create multiple objects and obtain different results.

The above is the detailed content of What is PHP object-oriented and the three major characteristics of object-oriented. For more information, please follow other related articles on the PHP Chinese website!

Statement

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

What is the difference between absolute and idle session timeouts?May 03, 2025 am 12:21 AM

Absolute session timeout starts at the time of session creation, while an idle session timeout starts at the time of user's no operation. Absolute session timeout is suitable for scenarios where strict control of the session life cycle is required, such as financial applications; idle session timeout is suitable for applications that want users to keep their session active for a long time, such as social media.

What steps would you take if sessions aren't working on your server?May 03, 2025 am 12:19 AM

The server session failure can be solved through the following steps: 1. Check the server configuration to ensure that the session is set correctly. 2. Verify client cookies, confirm that the browser supports it and send it correctly. 3. Check session storage services, such as Redis, to ensure that they are running normally. 4. Review the application code to ensure the correct session logic. Through these steps, conversation problems can be effectively diagnosed and repaired and user experience can be improved.

What is the significance of the session_start() function?May 03, 2025 am 12:18 AM

session_start()iscrucialinPHPformanagingusersessions.1)Itinitiatesanewsessionifnoneexists,2)resumesanexistingsession,and3)setsasessioncookieforcontinuityacrossrequests,enablingapplicationslikeuserauthenticationandpersonalizedcontent.

What is the importance of setting the httponly flag for session cookies?May 03, 2025 am 12:10 AM

Setting the httponly flag is crucial for session cookies because it can effectively prevent XSS attacks and protect user session information. Specifically, 1) the httponly flag prevents JavaScript from accessing cookies, 2) the flag can be set through setcookies and make_response in PHP and Flask, 3) Although it cannot be prevented from all attacks, it should be part of the overall security policy.

What problem do PHP sessions solve in web development?May 03, 2025 am 12:02 AM

PHPsessionssolvetheproblemofmaintainingstateacrossmultipleHTTPrequestsbystoringdataontheserverandassociatingitwithauniquesessionID.1)Theystoredataserver-side,typicallyinfilesordatabases,anduseasessionIDstoredinacookietoretrievedata.2)Sessionsenhances

What data can be stored in a PHP session?May 02, 2025 am 12:17 AM

PHPsessionscanstorestrings,numbers,arrays,andobjects.1.Strings:textdatalikeusernames.2.Numbers:integersorfloatsforcounters.3.Arrays:listslikeshoppingcarts.4.Objects:complexstructuresthatareserialized.

How do you start a PHP session?May 02, 2025 am 12:16 AM

TostartaPHPsession,usesession_start()atthescript'sbeginning.1)Placeitbeforeanyoutputtosetthesessioncookie.2)Usesessionsforuserdatalikeloginstatusorshoppingcarts.3)RegeneratesessionIDstopreventfixationattacks.4)Considerusingadatabaseforsessionstoragei

What is session regeneration, and how does it improve security?May 02, 2025 am 12:15 AM

Session regeneration refers to generating a new session ID and invalidating the old ID when the user performs sensitive operations in case of session fixed attacks. The implementation steps include: 1. Detect sensitive operations, 2. Generate new session ID, 3. Destroy old session ID, 4. Update user-side session information.

See all articles