PHP Constant
PHP constant is an identifier(name) for a simple value. The value does not change during the script. It starts with a letter or underscore not $ sign. The define()function is used to create a constant.
Syntax:
define(name, value, case-insensitive);Example:
<!DOCTYPE html>
<html>
<body>
<?php
// case-sensitive constant name
define("GREETING", "Welcome to PHP Tutorial");
echo GREETING;
?>
</body>
</html>
Output
Welcome to PHP Tutorial
Constants are Global
PHP constant is automatically global. It can be used for entire script.Let’s take an example.
Example
<?php
define("GREETING", "Welcome to PHP Tutorial");
functionmyTest() {
echo GREETING;
}
myTest();
?>