


PHP's `::` vs. `->`: When to Use Double Colon and Arrow for Method Access?
Dec 08, 2024 pm 07:59 PM`: When to Use Double Colon and Arrow for Method Access?
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Double Colon (::) and Arrow (->) in PHP: An Accessible Comparison
The PHP language offers two distinct methods for accessing methods: the double colon (::) and the arrow (->). While both serve the purpose of executing a function within a class, their usage and behavior have inherent differences.
:: (Double Colon)
The double colon signifies a static method call, which is directly associated with the class in question. It is employed for accessing properties and methods that exist within the class definition itself, irrespective of any instances of that class.
-> (Arrow)
The arrow notation, on the other hand, represents an instance method call. It allows access to properties and methods within an instance of a class, which is typically an object created based on that class. It necessitates the existence of an instance before it can be used.
Key Distinctions
- Static methods can be called without an instance of the class, while instance methods require an object.
- Static methods are shared among all instances of a class, while instance methods are specific to each object.
- Static methods can access static properties, while instance methods can access both static and instance properties.
Additional Considerations
- Arrow assignment (=>) is not involved in the context of accessing methods. It is used exclusively for assigning values within arrays.
- Variable assignment uses the equal sign (=) to initialize or modify a variable.
Example Usage
Consider the following code snippet:
class Person { public static $species = "human"; public function getName() { return $this->name; } }
In this example, Person::$species refers to the static property using the double colon notation, while $person->getName() accesses the instance method getName() using the arrow notation.
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