search
HomeBackend DevelopmentPHP TutorialSummary of common magic methods in php_php skills

This article organizes and summarizes the commonly used magic methods in PHP in detail and shares them with you for your reference. The specific content is as follows

1. PHP treats all methods starting with "__" as magic methods, so any custom methods cannot start with "__"
Overloading provided by PHP refers to dynamically creating attributes or methods. Overloading is achieved through magic methods. The parameters of these magic methods cannot be passed. __get(), __set(), __isset(), __unset() implements class attribute overloading.
2. When accessing an inaccessible attribute in a class, the __get() method will be called
3. When accessing inaccessible attributes in a class, __get(), __set(), __isset(), __unset() will be called according to different situations. When accessing attributes, use the function isset() or empty() When using the unset() function, the __isset() method will be called.
4. These four methods cannot be defined using the static keyword. After php5.3.0, a warning level warning will occur when the static method is used to define these four methods.
5. What are inaccessible attributes: (1) attributes that are not in the class, (2) private variables are accessed outside the class. Method overloading is implemented through __call() and __callstatic(). The difference between the two is whether a context is a static method. The latter will be called when an inaccessible static method is called. __callstatic() was added in php5.3.0.
6. __sleep() and __wakeup()
When serialize() is serializing, it will first check whether the __sleep() function exists. If it exists, it will first call __sleep() and return an array containing all variable names. If the method does not return anything, null will be serialized. ization and generate a notice-level error.
The __wakeup() method is the opposite of __sleep() and is called when unserialize() is called
7. __toString(), let a class decide how to convert it into a string. Before php5.2.0, this method can only be effective in combination with the echo or print method. After php5.2.0, it can be combined with printf() modification, but when modifying Non-character modifiers such as %d cannot be used.
8. __invoke(), when trying to call an object by calling a function, this function will be triggered. It only takes effect after php5.3.
9. __set_state() static method. This static method will only be called when var_export() is called. It will take effect after php5.1.0. The only parameter is to receive an array.
10. __construct() and __destruct(), constructor and destructor. The constructor is mainly used for class initialization. The destructor runs after all references to an object are deleted or when the object is explicitly destroyed. Exceptions are not allowed to be thrown in the destructor, otherwise a fatal error will be triggered. The destructor is called at the end of the script, when all http headers have been sent.
11. __clone(), object copy, this method cannot be called directly, it must be called explicitly through the clone keyword

Code:

//实例化对象时,会调用对象的__construct方法
$obj = new Object();
//给对象不存在的属性赋值时,会调用对象的__set方法
$obj->title = "hello";
//使用对象不存在的属性时,会调用对象的__get方法
echo $obj->title;
//调用对象不存在的方法时,会调用对象的__call方法
$obj->test("hello",123,567);
//调用不存在的类静态方法时,会调用类的__callStatic方法
Object::staticMethod("static","not found method");
//直接输出对象时,会调用对象的__toString方法
echo $obj;
//将一个对象当作函数一样使用时,会调用对象的__invoke方法
echo $obj("test");
//克隆对象时,会调用对象的__clone方法
$obj2 = clone $obj;
//判断对象属性是否存在时,会调用对象的__isset方法
var_dump(isset($obj->aaa));
//销毁对象属性时,会调用对象的__unset方法
unset($obj->aaa);
 
 
class Object{
 
  protected $array = array();
 
  function __construct()
  {
    echo __METHOD__."你正在实例化对象<br>";
  }
 
  function __set($name, $value)
  {
    $this->array[$name]=$value;
  }
 
  function __get($name)
  {
    return $this->array[$name];
  }
 
  function __call($name, $arguments)
  {
    var_dump($name,$arguments);
    return "magic function\n";
  }
 
  static function __callStatic($name, $arguments)
  {
    var_dump($name,$arguments);
    return "magic static function";
  }
 
  function __toString()
  {
    return __CLASS__.'<br>';
  }
 
  function __invoke($arguments)
  {
    var_dump($arguments);
    return __METHOD__.'<br>';
  }
 
  function __clone()
  {
    echo __METHOD__."你正在克隆对象<br>";
  }
 
  function __isset($name)
  {
    echo __METHOD__."你想判断有没有属性".$name."<br>";
    return 1;
  }
 
  function __unset($name)
  {
    echo __METHOD__."你想删除属性".$name."<br>";
  }
 
 
  function __destruct()
  {
    echo __METHOD__."你正在注销对象<br>";
  }
 
 
 
}

The above is all about the common magic methods in php. I hope it will be helpful to everyone's learning.

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
PHP and Python: Different Paradigms ExplainedPHP and Python: Different Paradigms ExplainedApr 18, 2025 am 12:26 AM

PHP is mainly procedural programming, but also supports object-oriented programming (OOP); Python supports a variety of paradigms, including OOP, functional and procedural programming. PHP is suitable for web development, and Python is suitable for a variety of applications such as data analysis and machine learning.

PHP and Python: A Deep Dive into Their HistoryPHP and Python: A Deep Dive into Their HistoryApr 18, 2025 am 12:25 AM

PHP originated in 1994 and was developed by RasmusLerdorf. It was originally used to track website visitors and gradually evolved into a server-side scripting language and was widely used in web development. Python was developed by Guidovan Rossum in the late 1980s and was first released in 1991. It emphasizes code readability and simplicity, and is suitable for scientific computing, data analysis and other fields.

Choosing Between PHP and Python: A GuideChoosing Between PHP and Python: A GuideApr 18, 2025 am 12:24 AM

PHP is suitable for web development and rapid prototyping, and Python is suitable for data science and machine learning. 1.PHP is used for dynamic web development, with simple syntax and suitable for rapid development. 2. Python has concise syntax, is suitable for multiple fields, and has a strong library ecosystem.

PHP and Frameworks: Modernizing the LanguagePHP and Frameworks: Modernizing the LanguageApr 18, 2025 am 12:14 AM

PHP remains important in the modernization process because it supports a large number of websites and applications and adapts to development needs through frameworks. 1.PHP7 improves performance and introduces new features. 2. Modern frameworks such as Laravel, Symfony and CodeIgniter simplify development and improve code quality. 3. Performance optimization and best practices further improve application efficiency.

PHP's Impact: Web Development and BeyondPHP's Impact: Web Development and BeyondApr 18, 2025 am 12:10 AM

PHPhassignificantlyimpactedwebdevelopmentandextendsbeyondit.1)ItpowersmajorplatformslikeWordPressandexcelsindatabaseinteractions.2)PHP'sadaptabilityallowsittoscaleforlargeapplicationsusingframeworkslikeLaravel.3)Beyondweb,PHPisusedincommand-linescrip

How does PHP type hinting work, including scalar types, return types, union types, and nullable types?How does PHP type hinting work, including scalar types, return types, union types, and nullable types?Apr 17, 2025 am 12:25 AM

PHP type prompts to improve code quality and readability. 1) Scalar type tips: Since PHP7.0, basic data types are allowed to be specified in function parameters, such as int, float, etc. 2) Return type prompt: Ensure the consistency of the function return value type. 3) Union type prompt: Since PHP8.0, multiple types are allowed to be specified in function parameters or return values. 4) Nullable type prompt: Allows to include null values ​​and handle functions that may return null values.

How does PHP handle object cloning (clone keyword) and the __clone magic method?How does PHP handle object cloning (clone keyword) and the __clone magic method?Apr 17, 2025 am 12:24 AM

In PHP, use the clone keyword to create a copy of the object and customize the cloning behavior through the \_\_clone magic method. 1. Use the clone keyword to make a shallow copy, cloning the object's properties but not the object's properties. 2. The \_\_clone method can deeply copy nested objects to avoid shallow copying problems. 3. Pay attention to avoid circular references and performance problems in cloning, and optimize cloning operations to improve efficiency.

PHP vs. Python: Use Cases and ApplicationsPHP vs. Python: Use Cases and ApplicationsApr 17, 2025 am 12:23 AM

PHP is suitable for web development and content management systems, and Python is suitable for data science, machine learning and automation scripts. 1.PHP performs well in building fast and scalable websites and applications and is commonly used in CMS such as WordPress. 2. Python has performed outstandingly in the fields of data science and machine learning, with rich libraries such as NumPy and TensorFlow.

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
1 months agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Best Graphic Settings
1 months agoBy尊渡假赌尊渡假赌尊渡假赌
Will R.E.P.O. Have Crossplay?
1 months agoBy尊渡假赌尊渡假赌尊渡假赌

Hot Tools

MinGW - Minimalist GNU for Windows

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.

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

WebStorm Mac version

WebStorm Mac version

Useful JavaScript development tools

Dreamweaver Mac version

Dreamweaver Mac version

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)