Class constant in php with example in 2022

Class constant in php with example in 2021

Class constant in php with example

Class Constant: constant is an element of class that can not be changed once it is declared. the const keyword is used to declare a constant. the constant can be accessed inside and outside a class. 

Outside a class, it can be accessed using scope resolution (::) symbol and class name. Inside a class, it can be accessed using self keyword and scope resolution (::) symbol.

Java Language

Accessing const outside a class: it is recommended to name the constants in all uppercase letters but it is not compulsory.

Python Language

How to use Accessing const outside a class in PHP?

<?php

class Student 

{

  const NAME= "Icoderweb";

  const ROLLNO=2021;

}

echo "Student Name:".Student::NAME."<br>";

echo "Student Rollno:".Student::ROLLNO."<br>";

?>

*****OUTPUT*****

Student Name:Icoderweb

Student Rollno:2021

Accessing const inside a class: const data can be accessed inside a class using self keyword and class name.

How to use Accessing const inside a class in php.

class Student 

{

  const NAME= "Icoderweb";

  const ROLLNO=2021;

  function intro()

  {

  echo "Student Name:".self::NAME."<br>";

  echo "Student Rollno:".self::ROLLNO."<br>";

  echo "Student Name:".Student::NAME."<br>";

  echo "Student Rollno:".Student::ROLLNO."<br>";

  }

}

$obj=new Student();

$obj->intro();

?>

*****OUTPUT*****

Student Name: Icoderweb

Student Rollno:2021

Student Name: Icoderweb

Student Rollno:2021