constant()

Introduction to the constant() Function

The constant() function in PHP is used to retrieve the value of a constant.

Usage of the constant() Function

The constant() function takes one argument, which is the name of the constant whose value is to be retrieved. The function returns the value of the constant.

Example Usage of the constant() Function

Here's an example of how the constant() function can be used in PHP:

Example Usage of the constant() Function

<‌?php

define("PI", 3.14159);

$radius = 5;

$area = constant("PI") * $radius * $radius;

echo "The area of a circle with radius $radius is $area.";

Try it Yourself »

In this example, the constant PI is defined with the value 3.14159. The constant() function is then used to retrieve the value of PI, which is then used to calculate the area of a circle.

Conclusion

In conclusion, the constant() function in PHP is a useful tool for retrieving the value of constants in your code. It is a simple function that takes one argument, the name of the constant, and returns its value.

Practice

What are the characteristics of PHP constants?

A constant is an identifier (name) for a simple value, as the name suggests, that value cannot be changed during the script.They can be defined and accessed anywhere without regard to variable scoping rules.PHP constants are case-sensitive.Unlike variables, Constants do not have a dollar sign ($) before them.You can change the value of PHP constant once it's defined.