PHP Constants

PHP Constants

A constant is an identifier (name) for a simple value. The value cannot be changed during the script.

A valid constant name starts with a letter or underscore (no $ sign before the constant name).

Note: Unlike variables, constants are automatically global across the entire script.

Create a PHP Constant

To create a constant, use the define() function.

Syntax: define(name, value)

PHP 7+ Constant Arrays

In PHP 7, you can create an array constant using the define() function.

PHP const Keyword

You can also use the const keyword to define constants.