How to use anonymous classes in PHP7
After PHP7, the anonymous class feature was added to PHP. Anonymous classes and anonymous methods make PHP a more modern language and make our code development work more and more convenient. Let's first look at the simple use of anonymous classes.
// 直接定义
$objA = new class
{
public function getName()
{
echo "I'm objA";
}
};
$objA->getName();
// 方法中返回
function testA()
{
return new class
{
public function getName()
{
echo "I'm testA's obj";
}
};
}
$objB = testA();
$objB->getName();
// 作为参数
function testB($testBobj)
{
echo $testBobj->getName();
}
testB(new class{
public function getName()
{
echo "I'm testB's obj";
}
});Three methods of using anonymous classes are given at once. Anonymous classes can be directly defined as variables, can be returned using return in methods, or can be passed as parameters to methods. In fact, an anonymous class is like a class that is not defined in advance, but is instantiated directly when it is defined.
// 继承、接口、访问控制等
class A
{
public $propA = 'A';
public function getProp()
{
echo $this->propA;
}
}
trait B
{
public function getName()
{
echo 'trait B';
}
}
interface C
{
public function show();
}
$p4 = 'b4';
$objC = new class($p4) extends A implements C
{
use B;
private $prop1 = 'b1';
protected $prop2 = 'b2';
public $prop3 = 'b3';
public function __construct($prop4)
{
echo $prop4;
}
public function getProp()
{
parent::getProp();
echo $this->prop1, '===', $this->prop2, '===', $this->prop3, '===', $this->propA;
$this->getName();
$this->show();
}
public function show()
{
echo 'show';
}
};
$objC->getProp();Anonymous classes, like ordinary classes, can inherit other classes, implement interfaces, and of course include various access control capabilities. In other words, anonymous classes are no different from ordinary classes in use. But if you use get_class() to get the class name, it will be the class name automatically generated by the system. The name returned by the same anonymous class is of course the same.
// 匿名类的名称是通过引擎赋予的
var_dump(get_class($objC));
// 声明的同一个匿名类，所创建的对象都是这个类的实例
var_dump(get_class(testA()) == get_class(testA()));
那么匿名类中的静态成员呢？当然也和普通类一样，静态成员是属于类而不是实例的。
// 静态变量
function testD()
{
return new class{
public static $name;
};
}
$objD1 = testD();
$objD1::$name = 'objD1';
$objD2 = testD();
$objD2::$name = 'objD2';
echo $objD1::$name;When the static variable in the class is modified, the static variable of all class instances will change accordingly. This is also the characteristic of static members of ordinary classes.
The above is the detailed content of How to use anonymous classes in PHP7. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undress AI Tool
Undress images for free
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
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
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
A Simple Guide to PHP Setup
Jul 18, 2025 am 04:25 AM
The key to setting up PHP is to clarify the installation method, configure php.ini, connect to the web server and enable necessary extensions. 1. Install PHP: Use apt for Linux, Homebrew for Mac, and XAMPP recommended for Windows; 2. Configure php.ini: Adjust error reports, upload restrictions, etc. and restart the server; 3. Use web server: Apache uses mod_php, Nginx uses PHP-FPM; 4. Install commonly used extensions: such as mysqli, json, mbstring, etc. to support full functions.
Commenting Out Code in PHP
Jul 18, 2025 am 04:57 AM
There are three common methods for PHP comment code: 1. Use // or # to block one line of code, and it is recommended to use //; 2. Use /.../ to wrap code blocks with multiple lines, which cannot be nested but can be crossed; 3. Combination skills comments such as using /if(){}/ to control logic blocks, or to improve efficiency with editor shortcut keys, you should pay attention to closing symbols and avoid nesting when using them.
Tips for Writing PHP Comments
Jul 18, 2025 am 04:51 AM
The key to writing PHP comments is to clarify the purpose and specifications. Comments should explain "why" rather than "what was done", avoiding redundancy or too simplicity. 1. Use a unified format, such as docblock (/*/) for class and method descriptions to improve readability and tool compatibility; 2. Emphasize the reasons behind the logic, such as why JS jumps need to be output manually; 3. Add an overview description before complex code, describe the process in steps, and help understand the overall idea; 4. Use TODO and FIXME rationally to mark to-do items and problems to facilitate subsequent tracking and collaboration. Good annotations can reduce communication costs and improve code maintenance efficiency.
Improving Readability with Comments
Jul 18, 2025 am 04:46 AM
The key to writing good comments is to explain "why" rather than just "what was done" to improve the readability of the code. 1. Comments should explain logical reasons, such as considerations behind value selection or processing; 2. Use paragraph annotations for complex logic to summarize the overall idea of functions or algorithms; 3. Regularly maintain comments to ensure consistency with the code, avoid misleading, and delete outdated content if necessary; 4. Synchronously check comments when reviewing the code, and record public logic through documents to reduce the burden of code comments.
Writing Effective PHP Comments
Jul 18, 2025 am 04:44 AM
Comments cannot be careless because they want to explain the reasons for the existence of the code rather than the functions, such as compatibility with old interfaces or third-party restrictions, otherwise people who read the code can only rely on guessing. The areas that must be commented include complex conditional judgments, special error handling logic, and temporary bypass restrictions. A more practical way to write comments is to select single-line comments or block comments based on the scene. Use document block comments to explain parameters and return values at the beginning of functions, classes, and files, and keep comments updated. For complex logic, you can add a line to the previous one to summarize the overall intention. At the same time, do not use comments to seal code, but use version control tools.
Learning PHP: A Beginner's Guide
Jul 18, 2025 am 04:54 AM
TolearnPHPeffectively,startbysettingupalocalserverenvironmentusingtoolslikeXAMPPandacodeeditorlikeVSCode.1)InstallXAMPPforApache,MySQL,andPHP.2)Useacodeeditorforsyntaxsupport.3)TestyoursetupwithasimplePHPfile.Next,learnPHPbasicsincludingvariables,ech
Quick PHP Installation Tutorial
Jul 18, 2025 am 04:52 AM
ToinstallPHPquickly,useXAMPPonWindowsorHomebrewonmacOS.1.OnWindows,downloadandinstallXAMPP,selectcomponents,startApache,andplacefilesinhtdocs.2.Alternatively,manuallyinstallPHPfromphp.netandsetupaserverlikeApache.3.OnmacOS,installHomebrew,thenrun'bre
Mastering PHP Block Comments
Jul 18, 2025 am 04:35 AM
PHPblockcommentsareusefulforwritingmulti-lineexplanations,temporarilydisablingcode,andgeneratingdocumentation.Theyshouldnotbenestedorleftunclosed.BlockcommentshelpindocumentingfunctionswithPHPDoc,whichtoolslikePhpStormuseforauto-completionanderrorche
