PHP constant() Function
Last Updated :
31 Dec, 2020
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The constant() function returns the value of a constant. It also works with class constants.
Syntax:
constant(constant)
Parameter Values:
- constant: It is a required value that specifies the value of the constant.
Return Value: It returns the value of a constant if the constant is defined else returns NULL.
Note: It works on PHP 4.0 or newer versions.
Exceptions: If the constant is not defined, it throws an E_WARNING error. It gives a run time warning without script termination.
The following are the PHP programs to show the working of the constant() function.
Example 1: Case sensitive
<?php
// Define a constant
define("Home","Welcome to GeeksforGeeks");
echo constant("Home");
?>
Output:
Welcome to GeeksforGeeks
Example 2: Case insensitive
<?php
// Define a case insensitive constant
define("GFGConstant","True denotes case-insensitive", true);
echo constant("gfgconstant");
?>
Output:
True denotes case-insensitive
Reference: https://www.php.net/manual/en/function.constant.php
