PHP | ReflectionClass getConstant() Function

The ReflectionClass::getConstant() function is an inbuilt function in PHP which is used to return the value of the defined constant.

Syntax:

mixed ReflectionClass::getConstant( string $name )

Parameters: This function accepts a parameter Name which is the name of the defined constant.

Return Value: This function returns the value of the defined constant.

Below programs illustrate the ReflectionClass::getConstant() function in PHP:

Program 1:

<?php

// Declaring a class named as Department
class Department {

    // Defining a constant
    const First = "CSE";

}

// Using the ReflectionClass() function
// over the Department class
$A = new ReflectionClass('Department');

// Calling the getConstant() function over
// First constant
$a = $A->getConstant('First');

// Getting the value of the defined constant
print_r($a);
?>

Output:

CSE

Program 2:

<?php

// Declaring a class named as Company
class Company {

    // Defining a constant
    const First = "GeeksforGeeks";
    const Second = "GFG";
    const Third = "gfg";

}

// Using the ReflectionClass() function
// over the Company class
$A = new ReflectionClass('Company');

// Calling the getConstant() function over
// the defined constants and
// getting the value of the defined constants
print_r($A->getConstant('First'));
echo("\n");
print_r($A->getConstant('Second'));
echo("\n");
print_r($A->getConstant('Third'));
?>

Output:

GeeksforGeeks
GFG
gfg

Reference: https://www.php.net/manual/en/reflectionclass.getconstant.php