How to call attributes and methods of a class in php

In object-oriented programming, class is a very important concept. A class can define member variables and member functions, and then use these variables and functions by instantiating objects. In PHP, we can use the keyword class to define a class. Next, I'll show you how to call the properties and methods of a class in PHP.

Call class attributes

The attributes of a class are member variables of the class, and they store data about the state of the object. To call the properties of a class in PHP, we can use an instantiation of an object to access those properties. Here is an example:

class Person {
  public $name = "";
  public $age = "";

  function set_name($name) {
    $this->name = $name;
  }

  function set_age($age) {
    $this->age = $age;
  }
}

$person = new Person;
$person->name = "Tom";
$person->age = 20;

echo $person->name;
echo $person->age;

We first define a Person class with two properties, $name and $age, and two methods, set_name and set_age, for setting properties. We then instantiate a $person object and set its properties using direct access. Finally, we use the echo statement to print out the properties of the $person object.

Calling class methods

The methods of a class are member functions of the class, used to perform operations and return data. To call methods of a class in PHP, we can use an instantiation of an object to call these methods. The following is an example:

class Person {
  public $name = "";
  public $age = "";

  function set_name($name) {
    $this->name = $name;
  }

  function set_age($age) {
    $this->age = $age;
  }

  function get_name() {
    return $this->name;
  }

  function get_age() {
    return $this->age;
  }

  function display_details() {
    echo "Name: " . $this->get_name() . ", Age: " . $this->get_age();
  }
}

$person = new Person;
$person->set_name("Tom");
$person->set_age(20);
$person->display_details();

We first define a Person class with attributes $name and $age, and four methods: set_name, set_age, get_name and get_age methods are used to access attributes, and the display_details method is used to Show person details. We then instantiate a $person object and use the set_name and set_age methods to set its properties, and finally use the display_details method to display the person details.

In this example, we use the get_name and get_age methods to return the attribute value. This is a form of data encapsulation because we can add other code within the method to calculate or manipulate the data without having external code use the properties directly. This also improves the security and maintainability of the code.

In summary, calling the properties and methods of a class is a very important step in object-oriented programming. You can easily access and manipulate the state of an object by instantiating it and using the object's instantiation to access properties and methods. In PHP, classes are also an important concept, which is of great significance to calling the properties and methods of classes in PHP.

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