PHP Constant Class

The const keyword is used to declare a class constant. A constant is unchangeable once it is declared. The constant class declared inside the class definition. The class constant is case-sensitive. However, it is recommended to name the constants in all uppercase letters. Constant differ from normal variables as no $ (dollar sign) is used. The default visibility of class constants is public. Class constants are useful when you need to declare some constant data (which does not change) within a class.

There are two ways to access class constant:

Outside the Class: The class constant is accessed by using the class name followed by the scope resolution operator (::) followed by the constant name.

Example:

PHP

<?php 
  
class code{ 
  
    // Declare const class 
    const Greetings = "Welcome to geeksforgeeks"; 
} 
  
// Access const class 
echo code::Greetings 
?> 