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What is the PHP ::class Notation and How Does it Simplify Class Handling?
What is the PHP ::class Notation and How Does it Simplify Class Handling?
Nov 22, 2024 am 06:09 AM
The ::class Notation in PHP: A Comprehensive Explanation
The ::class notation in PHP is a relatively recent addition to the language, introduced in version 5.5. This notation allows you to retrieve the fully qualified name of a class, including its namespace.
How to Use ::class
To use the ::class notation, simply write the name of the class followed by the ::class suffix:
SomeClass::class
This will return the full name of the class, such as:
App\Console\Commands\Inspire
Benefits of Using ::class
The ::class notation offers several advantages over traditional methods of storing class names:
- Eliminates the need for string literals: Instead of storing class names as strings, you can use the ::class notation, which will automatically generate the correct fully qualified name. This makes your code more robust and less error-prone.
- Improves IDE refactoring: Many IDEs can leverage the ::class notation to auto-complete class names and update them correctly during code refactoring.
- Simplifies usage with the use keyword: You can use the use keyword to alias class names, making it easier to work with them in your code. For example:
use App\Console\Commands\Inspire;
//...
protected $commands = [
Inspire::class, // Equivalent to "App\Console\Commands\Inspire"
];
Additional Applications of ::class
In addition to its primary function, the ::class notation can also be used for late static binding, a technique where the name of the derived class is resolved inside the parent class. This can be accomplished by using the static::class syntax:
class A {
public function getClassName(){
return __CLASS__;
}
public function getRealClassName() {
return static::class;
}
}
class B extends A {}
$a = new A;
$b = new B;
echo $a->getClassName(); // A
echo $a->getRealClassName(); // A
echo $b->getClassName(); // A
echo $b->getRealClassName(); // BThe above is the detailed content of What is the PHP ::class Notation and How Does it Simplify Class Handling?. For more information, please follow other related articles on the PHP Chinese website!
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