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).
Unlike variables, constants are automatically global across the entire script.
To set a constant, use the define() function.
Statement:
define(“GREETING”, “Welcome to W3Schools.com!”, true);
define(“constant name”, “constat value”, case-insensitive true/false);
<?php
// define a case-insensitive constant
define("GREETING", "Welcome to W3Schools.com!", true);
echo GREETING;
echo "<br>";
// will also output the value of the constant
echo greeting; // case-insensitive
?>
