How Do PHP\'s Object Operators (`->` and `::`) Work?

` and `::`) Work? " />

Object Operators in PHP

In PHP, we utilize object operators to interact with objects and leverage their properties and methods. There are two primary object operators:

1. Object Operator (>)

This operator allows us to access instance properties and invoke methods within an object. Its syntax is as follows:

$object->property;
$object->method();

For example, given the following class definition:

class Person {
    private $name;
    public function sayHello() {
        return "Hello, my name is " . $this->name;
    }
}

We can create an instance of this class and use the object operator to access its properties and invoke its methods:

$person = new Person();
$person->name = "John Doe";
echo $person->sayHello(); // Output: "Hello, my name is John Doe"

2. Static Object Operator (::)

This operator is used in three scenarios:

• Calling Static Methods: Static methods are defined using the static keyword and do not require an object instance. We can call them using the :: operator, followed by the method name.

class Math {
    public static function add($a, $b) {
        return $a + $b;
    }
}

$result = Math::add(5, 10); // Output: 15

• Accessing Static Variables: Static variables belong to the class itself, not to individual instances. We can access them using the :: operator.

class Counter {
    public static $count = 0;
    public function increment() {
        self::$count++;
    }
}

Counter::increment(); // Increment the static $count
echo Counter::$count; // Output: 1

• Calling Parent's Methods: When using inheritance, we can call a method from a parent class within a child class using the :: operator.

class Animal {
    public function move() {
        //...
    }
}

class Dog extends Animal {
    public function bark() {
        // Call the move() method from the parent class using ::
        parent::move();
    }
}

The above is the detailed content of How Do PHP\'s Object Operators (`->` and `::`) Work?. For more information, please follow other related articles on the PHP Chinese website!